You searched for subject:(Scramjet).
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Virginia Tech
1.
Burger, Scott Kuhlman.
Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow.
Degree: MS, Aerospace and Ocean Engineering, 2010, Virginia Tech
URL: http://hdl.handle.net/10919/31981 
► This study examines the effect of varying injectant molecular weight on the penetration of transverse injection jets into a supersonic crossflow. The injectants considered here…
(more)
▼ This study examines the effect of varying injectant molecular weight on the penetration of transverse injection jets into a supersonic crossflow. The injectants considered here are methane (W=16.04), air (W=28.97) and carbon dioxide, (W=44.01). These results augment the previous results obtained at Virginia Tech for helium (W=4.00) injection under the same test conditions to provide a very wide range of molecular weights. Second, since shocks are ubiquitous in
scramjet combustors, their influence on penetration and mixing was also studied by arranging for an oblique shock to impinge near the injection station. The cases of a shock impinging upstream and downstream of the injector were both examined. One can anticipate an important influence of molecular weight here also because of the importance of density gradients on the generation of vorticity by baroclinic torque. Increasing molecular weight was found to increase penetration in general, as well as increase the lateral spreading of the plume. The majority of the data shows a weak dependency of the jet size on molecular weight, but there are indications that under certain circumstances large changes in the flow structure may occur due to molecular weight effects. The addition of an impinging shock is found to increase mixing and decrease penetration and plume size, especially with the shock impinging downstream of the injector.
Advisors/Committee Members: Schetz, Joseph A. (committeechair), Kochersberger, Kevin Bruce (committee member), Devenport, William J. (committee member).
Subjects/Keywords: molecular weight; mixing; injection; scramjet
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APA (6th Edition):
Burger, S. K. (2010). Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/31981
Chicago Manual of Style (16th Edition):
Burger, Scott Kuhlman. “Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow.” 2010. Masters Thesis, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/31981.
MLA Handbook (7th Edition):
Burger, Scott Kuhlman. “Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow.” 2010. Web. 18 Jun 2019.
Vancouver:
Burger SK. Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow. [Internet] [Masters thesis]. Virginia Tech; 2010. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/31981.
Council of Science Editors:
Burger SK. Investigation of Injectant Molecular Weight and Shock Impingement Effects on Transverse Injection Mixing in Supersonic Flow. [Masters Thesis]. Virginia Tech; 2010. Available from: http://hdl.handle.net/10919/31981
University of Minnesota
2.
Tylczak, Erik.
Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow.
Degree: PhD, Aerospace Engineering and Mechanics, 2016, University of Minnesota
URL: http://hdl.handle.net/11299/182745
► The interaction of multiple jets in supersonic crossflow is simulated using hybrid Reynolds- Averaged Navier Stokes and Large Eddy Simulation turbulence models. The blockage of…
(more)
▼ The interaction of multiple jets in supersonic crossflow is simulated using hybrid Reynolds- Averaged Navier Stokes and Large Eddy Simulation turbulence models. The blockage of a jet generates a curved bow shock, and in multi-jet flows, each shock impinges on the other fuel plumes. The curved nature of each shock generates vorticity directly, and the impingement of each shock on the vortical structures within the adjacent fuel plumes strengthens vortical structures already present. These stirring motions are the major driver of fuel-air mixing, and so mixing enhancement is predicted to occur in multi-port configurations. The primary geometry considered is that of the combustion duct at the Calspan- University of Buffalo Research Center 48” Large Energy National Shock (LENS) tunnel. This geometry was developed to be representative of the geometry and flow physics of the Flight 2 test vehicle of the Hypersonic International Flight Research Experimenta- tion Program (HiFIRE-2). This geometry takes the form of a symmetric pair of external compression ramps that feed an isolator of approximately 4” × 1” cross-section. Nine interdigitated flush-wall injectors, four on one wall and five on the other, inject hydrogen at an angle of 30 degrees to the freestream. Two freestream flow conditions are consid- ered: approximately Mach 7.2 at a static temperature of 214K and a density of 0.039 kg/m3 for the five-injector case, and approximately Mach 8.9 at a static temperature of 167K and density of 0.014 kg/m3 for the nine-injector case. Validation computations are performed on a single-port experiment with an imposed shock wave. Unsteady calculations are performed on five-port and nine-port configura- tions, and the five-port configuration is compared to calculations performed with only a single active port on the same geometry. Analysis of statistical data demonstrates enhanced mixing in the multi-port configurations in regions where shock impingement occurs.
Subjects/Keywords: CFD; Crossflow; Injection; Mixing; Scramjet
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APA (6th Edition):
Tylczak, E. (2016). Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/182745
Chicago Manual of Style (16th Edition):
Tylczak, Erik. “Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow.” 2016. Doctoral Dissertation, University of Minnesota. Accessed June 18, 2019.
http://hdl.handle.net/11299/182745.
MLA Handbook (7th Edition):
Tylczak, Erik. “Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow.” 2016. Web. 18 Jun 2019.
Vancouver:
Tylczak E. Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow. [Internet] [Doctoral dissertation]. University of Minnesota; 2016. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/11299/182745.
Council of Science Editors:
Tylczak E. Computational Study of Shock/Plume Interactions Between Multiple Jets in Supersonic Crossflow. [Doctoral Dissertation]. University of Minnesota; 2016. Available from: http://hdl.handle.net/11299/182745
University of Notre Dame
3.
Brock E. Hedlund.
Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>.
Degree: MSin Aerospace Engineering, Aerospace and Mechanical Engineering, 2018, University of Notre Dame
URL: https://curate.nd.edu/show/d791sf2933j
► This thesis documents the efforts to characterize the Mach 4.5 flow over a flat plate model with a 30° compression ramp over a range…
(more)
▼ This thesis documents the efforts to
characterize the Mach 4.5 flow over a flat plate model with a 30°
compression ramp over a range of unit Reynolds numbers (Rel = 4‧105
– 1‧107 m-1) in low enthalpy (T0 = 293 K) and high enthalpy (T0 =
800 – 1250 K) flow conditions. The compression ramp model was
designed, fabricated, and implemented in a hypersonic test facility
(ACT-1) to simulate small-scale
scramjet inlet operation. Flow
visualization was provided by a schlieren imaging system and planar
laser Rayleigh scattering (PLRS) to characterize the flow structure
with various Rel. Three measurement methods were used to determine
the frequency spectrum of flow perturbations: a high-frequency
Shack-Hartmann wavefront sensor, a laser differential
interferometer, and high-frequency pressure sensors. All three
methods provide complementary results to indicate the existence of
dominant frequencies of perturbations in the flow. It is determined
that of these three measurement tools, Shack-Hartmann wavefront
sensing is the most beneficial for this flow analysis. These
measurements detect modification to the flow perturbation spectra
during plasma actuation and across varied Rel. Damping of the
perturbations in certain frequency bands occurred in the spectra of
measurements taken in the corner separation bubble. In this way,
the spectra indicate dominant frequency bands of perturbations
occurring in regions of the boundary layer and separation bubble.
It is shown, that in the highest tested Rel cases, initial
disturbances in the freestream develop into strong perturbations,
which significantly affect the boundary layer and separation zone
size over the compression ramp. Both amplification and damping
effects from the natural state are seen within different bands of
the spectra of perturbations measured within the flow occurring
over the separation region of the compression ramp collected during
high-frequency plasma actuation (100 kHz). The amplification
observed leads to a fast laminar to turbulent transition
immediately after flow reattachment and potential stabilization of
the shock wave structure. This effect was not observed at F = 50
kHz plasma pulsing frequency.
Advisors/Committee Members: Seong-Kyun Im, Committee Member, Stanislav Gordeyev, Committee Member, Sergey Leonov, Research Director.
Subjects/Keywords: Flow Measurement; Scramjet; Hypersonic
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APA (6th Edition):
Hedlund, B. E. (2018). Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>. (Masters Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/d791sf2933j
Chicago Manual of Style (16th Edition):
Hedlund, Brock E.. “Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>.” 2018. Masters Thesis, University of Notre Dame. Accessed June 18, 2019.
https://curate.nd.edu/show/d791sf2933j.
MLA Handbook (7th Edition):
Hedlund, Brock E.. “Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>.” 2018. Web. 18 Jun 2019.
Vancouver:
Hedlund BE. Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>. [Internet] [Masters thesis]. University of Notre Dame; 2018. [cited 2019 Jun 18].
Available from: https://curate.nd.edu/show/d791sf2933j.
Council of Science Editors:
Hedlund BE. Measurement of Flow Perturbations Occurring Both Naturally
and by Plasma Induction over a Mach 4.5 Corner Separation
Zone</h1>. [Masters Thesis]. University of Notre Dame; 2018. Available from: https://curate.nd.edu/show/d791sf2933j
Penn State University
4.
Li, Jian.
IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING.
Degree: PhD, Mechanical Engineering, 2008, Penn State University
URL: https://etda.libraries.psu.edu/catalog/9560
► This research focuses on the modeling and simulation of ignition transient and subsequent combustion dynamics in an ethylene fueled supersonic combustion ramjet (scramjet) engine. The…
(more)
▼ This research focuses on the modeling and simulation
of ignition transient and subsequent combustion dynamics in an
ethylene fueled supersonic combustion ramjet (scramjet) engine. The
primary objectives are: 1) to establish an efficient and accurate
numerical framework for the treatment of unsteady flow and flame
dynamics in scramjet propulsion systems; and 2) to investigate the
effects of transverse air throttling on flow development and
fuel-air mixing, and to identify its positive influence on ignition
and flameholding in a scramjet combustor; and 3) to construct a
detailed study investigating ignition transient to identify
underlying essential mechanisms by means of air throttling
implementation technique. A comprehensive numerical study of the
combustion dynamics in a scramjet combustor is performed. The
analysis treats the conservation equations in three dimensions and
takes into account finite-rate chemical reactions and variable
thermophysical properties for a multi-component reacting flow.
Menter’s k-ω SST two-equation turbulence model is
implemented, as it performs well for shear-layer flows and wall
turbulence effects. The governing equations and the associated
boundary conditions are solved using a density-based finite-volume
approach and four-stage Runge-Kutta scheme to utilize explicit time
marching. The code is parallelized using the domain decomposition
technique and message passing interface (MPI). The theoretical
formulation and numerical scheme is first validated with two test
cases including turbulent flow over a flat plat and a
two-dimensional oblique shock wave, and then validated with engine
test data. The analysis is first employed to a detailed
investigation into the flow development and fuel-air mixing in the
scramjet engine for non-reacting flow at Mach 5 flight condition.
As the air throttling is implemented to increase the combustor
pressure, a series of subsequent oblique shock waves following the
fuel injectors is generated to separate the wall boundary layer,
and lead to a dramatic increase in the fuel/air mixing. The
detailed investigation reveals enhanced fuel-air mixing primarily
results from elevated vorticity over combustor and cavity, as well
as from increased residence time. Effort is then expended to study
the ignition and subsequent reacting flow in the modeled combustor.
The ignition transient and flame development are comprehensively
studied to investigate the influence of air throttling
implementation on ignition and flameholding. The time history of
combustion indicates that the engine model can hardly offer the
ignition under the given flight condition in the absence of air
throttling, as the ignition of ethylene fuel flow on the cowl
surface fails to be initiated. Calculation is then employed to
demonstrate the significant flow accommodation induced by air
throttling implementation, including subsequent decrease in flow
velocity and increases in temperature and pressure in the
combustor. Autoignition occurs on the cowl surface due to extended
residence time and…
Subjects/Keywords: supersonic combustion; Scramjet; CFD; air
throttling
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APA (6th Edition):
Li, J. (2008). IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/9560
Chicago Manual of Style (16th Edition):
Li, Jian. “IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING.” 2008. Doctoral Dissertation, Penn State University. Accessed June 18, 2019.
https://etda.libraries.psu.edu/catalog/9560.
MLA Handbook (7th Edition):
Li, Jian. “IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING.” 2008. Web. 18 Jun 2019.
Vancouver:
Li J. IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING. [Internet] [Doctoral dissertation]. Penn State University; 2008. [cited 2019 Jun 18].
Available from: https://etda.libraries.psu.edu/catalog/9560.
Council of Science Editors:
Li J. IGNITION TRANSIENT IN AN ETHYLENE FUELED SCRAMJET ENGINE
WITH AIR THROTTLING. [Doctoral Dissertation]. Penn State University; 2008. Available from: https://etda.libraries.psu.edu/catalog/9560
University of Toronto
5.
Chan, Jonathan.
Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11.
Degree: 2010, University of Toronto
URL: http://hdl.handle.net/1807/25446
► This study investigates the design and aeropropulsive performance of a complete, hydrogen powered, shock-induced combustion ramjet (shcramjet) at a flight Mach number of 11 and…
(more)
▼ This study investigates the design and aeropropulsive performance of a complete, hydrogen powered, shock-induced combustion ramjet (shcramjet) at a flight Mach number of 11 and altitude of 34.5 km. The design includes a Prandtl-Meyer compression inlet, cantilevered ramp fuel injectors, a shock-inducing wedge and a divergent nozzle. Numerical studies are undertaken using the WARP code that solves the three-dimensional Favre-averaged Navier-Stokes equations closed by the Wilcox k-ω turbulence model and the Jachimowski H2/air chemical kinetics model. Studies of fuel injection properties, mixing duct length, combustor wedge and nozzle geometry are completed to maximize the overall performance of the vehicle. The final shcramjet configuration generates a specific impulse of 1110 s. A comparison is undertaken with a scramjet vehicle at identical flight conditions and using many of the same components. The comparable scramjet generates a higher specific impulse of 1450 s although it is significantly larger and therefore heavier.
MAST
Advisors/Committee Members: Sislian, Jean Pascal, Aerospace Science and Engineering.
Subjects/Keywords: hypersonic; propulsion; scramjet; shcramjet; performance; simulation; 0538
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APA (6th Edition):
Chan, J. (2010). Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/25446
Chicago Manual of Style (16th Edition):
Chan, Jonathan. “Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11.” 2010. Masters Thesis, University of Toronto. Accessed June 18, 2019.
http://hdl.handle.net/1807/25446.
MLA Handbook (7th Edition):
Chan, Jonathan. “Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11.” 2010. Web. 18 Jun 2019.
Vancouver:
Chan J. Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11. [Internet] [Masters thesis]. University of Toronto; 2010. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1807/25446.
Council of Science Editors:
Chan J. Numerically Simulated Comparative Performance of a Scramjet and Shcramjet at Mach 11. [Masters Thesis]. University of Toronto; 2010. Available from: http://hdl.handle.net/1807/25446
Clemson University
6.
Quinones, Matthew.
Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers.
Degree: MS, Mechanical Engineering, 2018, Clemson University
URL: https://tigerprints.clemson.edu/all_theses/3010
► Various types of air breathing engines are used as propulsion devices in aviation. At high flight velocities, the use of a ramjet or supersonic combustion…
(more)
▼ Various types of air breathing engines are used as propulsion devices in aviation. At high
flight velocities, the use of a ramjet or supersonic combustion ramjet (
scramjet) may be
preferred due to the natural compressibility of air at high speed. A
scramjet, while
similar to the ramjet, does not slow air to subsonic speeds prior to combustion, allowing
it to operate at much higher flight velocities at very high altitude. For this reason,
however, the residence time of air inside of the combustor is on the order of milliseconds,
requiring rapid mixing and ignition of the fuel to generate adequate thrust. To do this, a
flameholder is often used, which generates turbulence, shock waves, and maintains a
recirculation region through geometric effects. In this study, four geometry types
involving eighteen separate designs were chosen and analyzed using CFD software.
Isolator inlet Mach numbers of 2.2, 4, 6, 8, and 10 were selected to model varying flight
velocity, and hydrogen fuel was injected sonically at all injector locations with a single
step reaction mechanism applied for combustion. An existing square cavity model was
chosen and modified to produce slanted cavity, double cavity, and combined strut-cavity
designs. The flameholders were analyzed in a non-reacting simulation to observe their
effects on the flow field and fuel mixing efficiency. Reacting simulations were
performed for each flameholder to investigate flame stabilization capabilities, thermal
choking, stagnation pressure losses and drag generated inside of the combustor. Results
show that all designs sustain a flame during combustion at all flight Mach numbers.
However, the square cavity with a back cavity injector does this while limiting losses and
drag due to shock wave formation, thermal choking, and geometric effects in the flow.
Advisors/Committee Members: Dr. Richard Miller, Committee Chair, Dr. John Saylor, Dr. Xiangchun Xuan.
Subjects/Keywords: Flame holder; Flame stability; Ramjet; Scramjet
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APA (6th Edition):
Quinones, M. (2018). Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers. (Masters Thesis). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_theses/3010
Chicago Manual of Style (16th Edition):
Quinones, Matthew. “Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers.” 2018. Masters Thesis, Clemson University. Accessed June 18, 2019.
https://tigerprints.clemson.edu/all_theses/3010.
MLA Handbook (7th Edition):
Quinones, Matthew. “Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers.” 2018. Web. 18 Jun 2019.
Vancouver:
Quinones M. Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers. [Internet] [Masters thesis]. Clemson University; 2018. [cited 2019 Jun 18].
Available from: https://tigerprints.clemson.edu/all_theses/3010.
Council of Science Editors:
Quinones M. Numerical Analysis of Scramjet Cavity Flameholders at Varying Flight Mach Numbers. [Masters Thesis]. Clemson University; 2018. Available from: https://tigerprints.clemson.edu/all_theses/3010
North Carolina State University
7.
Keistler, Patrick G.
A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications.
Degree: PhD, Aerospace Engineering, 2009, North Carolina State University
URL: http://www.lib.ncsu.edu/resolver/1840.16/3373
► A turbulence model that allows for the calculation of the variable turbulent Prandtl (Prt) and Schmidt (Sct) numbers as part of the solution is presented.…
(more)
▼ A turbulence model that allows for the calculation of the variable turbulent Prandtl (Prt) and Schmidt (Sct) numbers as part of the solution is presented. The model also accounts for the interactions between turbulence and chemistry by modeling the corresponding terms. Four equations are added to the baseline k-ζ turbulence model: two equations for enthalpy variance and its dissipation rate to calculate the turbulent diffusivity, and two equations for the concentrations variance and its dissipation rate to calculate the turbulent diffusion coefficient. The underlying turbulence model already accounts for compressibility effects. The variable Prt/Sct turbulence model is validated and tuned by simulating a wide variety of experiments. Included in the experiments are two-dimensional, axisymmetric, and three-dimensional mixing and combustion cases. The combustion cases involved either hydrogen and air, or hydrogen, ethylene, and air. Two chemical kinetic models are employed for each of these situations. For the hydrogen and air cases, a seven species/seven reaction model where the reaction rates are temperature dependent and a nine species/nineteen reaction model where the reaction rates are dependent on both pressure and temperature are used. For the cases involving ethylene, a 15 species/44 reaction reduced model that is both pressure and temperature dependent is used, along with a 22 species/18 global reaction reduced model that makes use of the quasi-steady-state approximation.
In general, fair to good agreement is indicated for all simulated experiments. The turbulence/chemistry interaction terms are found to have a significant impact on flame location for the two-dimensional combustion case, with excellent experimental agreement when the terms are included. In most cases, the hydrogen chemical mechanisms behave nearly identically, but for one case, the pressure dependent model would not auto-ignite at the same conditions as the experiment and the other chemical model. The model was artificially ignited in that case. For the cases involving ethylene combustion, the chemical model has a profound impact on the flame size, shape, and ignition location. However, without quantitative experimental data, it is difficult to determine which one is more suitable for this particular application.
Advisors/Committee Members: Fred R. DeJarnette, Committee Member (advisor), Jack R. Edwards, Committee Member (advisor), Hassan A. Hassan, Committee Chair (advisor), Pierre A. Gremaud, Committee Member (advisor).
Subjects/Keywords: scramjet; schmidt; prandtl; turbulence modeling; cfd
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Manager
APA (6th Edition):
Keistler, P. G. (2009). A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/3373
Chicago Manual of Style (16th Edition):
Keistler, Patrick G. “A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications.” 2009. Doctoral Dissertation, North Carolina State University. Accessed June 18, 2019.
http://www.lib.ncsu.edu/resolver/1840.16/3373.
MLA Handbook (7th Edition):
Keistler, Patrick G. “A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications.” 2009. Web. 18 Jun 2019.
Vancouver:
Keistler PG. A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications. [Internet] [Doctoral dissertation]. North Carolina State University; 2009. [cited 2019 Jun 18].
Available from: http://www.lib.ncsu.edu/resolver/1840.16/3373.
Council of Science Editors:
Keistler PG. A Variable Turbulent Prandtl and Schmidt Number Model Study for Scramjet Applications. [Doctoral Dissertation]. North Carolina State University; 2009. Available from: http://www.lib.ncsu.edu/resolver/1840.16/3373
University of New South Wales
8.
Van Pelt, Hilbert.
Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle.
Degree: Aerospace & Mechanical Engineering, 2018, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/60744
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:53083/SOURCE02?view=true
► Shock vector control (SVC) is a technique to control airplanes and spaceplanes by means of fluidinjection into the nozzle flow. SVC is part of fluidic…
(more)
▼ Shock vector control (SVC) is a technique to control airplanes and spaceplanes by means of fluidinjection into the nozzle flow. SVC is part of fluidic thrust vectoring, a technique whereby acontrol force can be generated by means of fluid injection in the engine exhaust.For this thesis the application of shock vector control to a converging-diverging nozzle and ahypersonic vehicle was investigated. The experiments with a converging-diverging nozzle withan injector took place in an experimental facility which houses extruded two-dimensional nozzleprofiles of 8 mm thick. The profiles are sealed by two windows on either side of the nozzle foroptical access. The nozzle is a linear converging-diverging nozzle with a sonic injector placed at71% length of the diverging section. On this geometry two-dimensional steady state simulationshave been performed, as well as time accurate simulations and a large eddy simulation. It isshown that the injected mass creates a blockage for the incoming flow generating a shock wave.This blockage causes the core flow to separate before the injector, meaning that there is a highpressure region before the injector creating the sideforce. It was demonstrated numerically andexperimentally that the sideforce, relative to the axial force, has a linear relationship with theinjected mass until the shock wave hits the opposite nozzle wall causing a shockwave boundarylayer interaction that is detrimental to the net sideforce.It is shown that this type of nozzle flow can be modelled with analytical relations based onblast wave theory. The established analytical methods were calibrated based on an orifice injectorand therefore the calibration constant needed to be changed from 1.2 to 2.36 because of the fullwidth injector. In an orifice injector the cross flow can go around the injected fluid, while in atwo-dimensional flow case all the nozzle flow is being turned by the injected fluid, and thereforethe calibration constant needs to be increased.It was demonstrated that for the small scale experiment the force establishment time is 0.2msec, which is faster than most solenoid valves available on the market. Analytically it is shownthat the establishment time will increase with the size of the nozzle, but it will remain fast enoughto be used as a control system for a full scale rocket or
scramjet.The experimental supersonic geometry was modelled with Large eddy simulation (LES) andcompared to Reynolds averaged Navier-Stokes (RANS) simulations. It was shown that the flowshows three-dimensional effects at the point where the sidewall meets the injector, but is moreiiitwo-dimensional towards the middle of the nozzle.To test the hypersonic implementation of SVC a
scramjet of similar shape to the X-43 wasdesigned with a single slot injector close to the trailing edge of the nozzle. The pressure in thehypersonic environment is orders of magnitude lower than in the supersonic experiment and thereforea large expansion of the Mach disk at the injection point was seen. An increase of sideforceand moment is present…
Advisors/Committee Members: Neely, Andrew James, Aerospace & Mechanical Engineering, UNSW Canberra, UNSW, Young, John, Aerospace & Mechanical Engineering, UNSW Canberra, UNSW.
Subjects/Keywords: Scramjet; Thrust vectoring; Shock vector control
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APA (6th Edition):
Van Pelt, H. (2018). Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/60744 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:53083/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Van Pelt, Hilbert. “Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle.” 2018. Doctoral Dissertation, University of New South Wales. Accessed June 18, 2019.
http://handle.unsw.edu.au/1959.4/60744 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:53083/SOURCE02?view=true.
MLA Handbook (7th Edition):
Van Pelt, Hilbert. “Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle.” 2018. Web. 18 Jun 2019.
Vancouver:
Van Pelt H. Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle. [Internet] [Doctoral dissertation]. University of New South Wales; 2018. [cited 2019 Jun 18].
Available from: http://handle.unsw.edu.au/1959.4/60744 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:53083/SOURCE02?view=true.
Council of Science Editors:
Van Pelt H. Shock Vector Control applied to a Converging-Diverging Nozzle and a Hypersonic Vehicle. [Doctoral Dissertation]. University of New South Wales; 2018. Available from: http://handle.unsw.edu.au/1959.4/60744 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:53083/SOURCE02?view=true
University of New South Wales
9.
Brieschenk, Stefan.
Laser-Induced Plasma Ignition Studies for Scramjet Propulsion.
Degree: Engineering & Information Technology, 2012, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/52252
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10922/SOURCE02?view=true
► An experimental investigation of the characteristics of laser-induced plasma (LIP)ignition for scramjet propulsion is presented. This work demonstrates for the first time, that LIP can…
(more)
▼ An experimental investigation of the characteristics of laser-induced plasma (LIP)ignition for
scramjet propulsion is presented. This work demonstrates for the first time, that LIP can be used to promote the formation of hydroxyl radicals (OH) in a hydrogen fuelled, hypersonic
scramjet. The experimental campaign was conducted in the free-piston shock tunnel T-ADFA at the Australian Defence Force Academy. A rectangular-duct
scramjet model with inlet injection, is used in the study. Two ignitionmethodologies are investigated. A Q-switched laser is used to generate LIP either in theshear layers (referred to in this document as shear-layer LIP ignition) at the injectorsite or inside the sonic throat of a single fuel injector (fuel-jet LIP ignition). Time-integrated chemiluminescence imaging of OH was used to investigate autoignition and radical-farming characteristics. The laser-induced fluorescence technique on the nitric oxide molecule (NO PLIF) is used for flow visualisation as well as two-line thermometry measurements. The temporal evolution of the LIP ignition process is visualised using the OH PLIF technique. The influence of using hydrogen fuel diluted with argon to serve as a plasma buffer, extending plasma lifetimes, is also investigated. The broadband self-luminosity signal of the LIP in the early stages immediately after laser initiation is recorded and used in combination with blast wave theory to obtain several conditions through which the LIP can be approximated in future computational fluid dynamic simulations of the LIP ignition process. The evolution of laser-induced plasmas in hydrogen, argon and air has been investigated as a function of pressure and laser energy using time-resolved schlieren visualisations in a gas cell. Time-resolved plasma spectroscopic temperature measurements have been conducted to investigate the effect of LIP confinement in a cylindrical reflector.
Advisors/Committee Members: O'Bryne, Sean, Engineering & Information Technology, UNSW Canberra, UNSW, Kleine, Harald, Engineering & Information Technology, UNSW Canberra, UNSW.
Subjects/Keywords: Scramjet propulsion; Laser-induced plasma ignition
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APA (6th Edition):
Brieschenk, S. (2012). Laser-Induced Plasma Ignition Studies for Scramjet Propulsion. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52252 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10922/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Brieschenk, Stefan. “Laser-Induced Plasma Ignition Studies for Scramjet Propulsion.” 2012. Doctoral Dissertation, University of New South Wales. Accessed June 18, 2019.
http://handle.unsw.edu.au/1959.4/52252 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10922/SOURCE02?view=true.
MLA Handbook (7th Edition):
Brieschenk, Stefan. “Laser-Induced Plasma Ignition Studies for Scramjet Propulsion.” 2012. Web. 18 Jun 2019.
Vancouver:
Brieschenk S. Laser-Induced Plasma Ignition Studies for Scramjet Propulsion. [Internet] [Doctoral dissertation]. University of New South Wales; 2012. [cited 2019 Jun 18].
Available from: http://handle.unsw.edu.au/1959.4/52252 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10922/SOURCE02?view=true.
Council of Science Editors:
Brieschenk S. Laser-Induced Plasma Ignition Studies for Scramjet Propulsion. [Doctoral Dissertation]. University of New South Wales; 2012. Available from: http://handle.unsw.edu.au/1959.4/52252 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10922/SOURCE02?view=true
Vanderbilt University
10.
Grady, Nathan Ryan.
Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut.
Degree: MS, Mechanical Engineering, 2010, Vanderbilt University
URL: http://etd.library.vanderbilt.edu/available/etd-12102010-144923/
;
► Supersonic air flow over a wall cavity with a rear ramp both with and without an upstream strut was studied with Hydroxyl Tagging Velocimetry (HTV).…
(more)
▼ Supersonic air flow over a wall cavity with a rear ramp both with and without an upstream strut was studied with Hydroxyl Tagging Velocimetry (HTV). HTV is a non-intrusive means of measuring gas velocity by producing a hydroxyl tag from water vapor via a two step process: 1) the âwriteâ phase where water molecules are dissociated into OH+H, 2) the âreadâ phase where after a fixed time delay the OH field is interrogated with planar laser-induced fluorescence. An 11x11 OH grid was used to obtain velocities at ~120 grid points. Mean and RMS fluctuation velocity profiles both with and without the strut were analyzed and compared to each other and to a rectangular cavity studied by other authors. In the ramped-cavity, increased recirculation and turbulence was observed over the ramp compared to the rectangular cavity, and the shear layer both grew slower and was lower into the cavity. Once the strut was installed, it was observed that cavity recirculation along the centerline increased relative to the no-strut configuration and extended above the step. Furthermore, expansion waves off the top of the strut and weak compression waves off the back of the strut were observed.
To best analyze vorticity, two separate interpolation schemes were interrogated by comparing velocity, and vorticity data. In general, the two methods provided similar results for irrotational flows. However for rotational flows, it was found that a Powell-Sabin interpolation more accurately determined the location of velocity gradients compared to a cubic interpolation scheme.
Advisors/Committee Members: Amrutur V. Anilkumar (committee member), Joseph A Wehrmeyer (committee member), Robert W. Pitz (chair).
Subjects/Keywords: strut; cavity; laser; HTV; supersonic; scramjet
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APA (6th Edition):
Grady, N. R. (2010). Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut. (Masters Thesis). Vanderbilt University. Retrieved from http://etd.library.vanderbilt.edu/available/etd-12102010-144923/ ;
Chicago Manual of Style (16th Edition):
Grady, Nathan Ryan. “Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut.” 2010. Masters Thesis, Vanderbilt University. Accessed June 18, 2019.
http://etd.library.vanderbilt.edu/available/etd-12102010-144923/ ;.
MLA Handbook (7th Edition):
Grady, Nathan Ryan. “Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut.” 2010. Web. 18 Jun 2019.
Vancouver:
Grady NR. Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut. [Internet] [Masters thesis]. Vanderbilt University; 2010. [cited 2019 Jun 18].
Available from: http://etd.library.vanderbilt.edu/available/etd-12102010-144923/ ;.
Council of Science Editors:
Grady NR. Hydroxyl Tagging Velocimetry in a Supersonic Flow Over a Ramped-Wall Cavity Flameholder with an Upstream Strut. [Masters Thesis]. Vanderbilt University; 2010. Available from: http://etd.library.vanderbilt.edu/available/etd-12102010-144923/ ;
Georgia Tech
11.
Miki, Kenji.
Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion.
Degree: PhD, Aerospace Engineering, 2009, Georgia Tech
URL: http://hdl.handle.net/1853/26605
► The main objective of this thesis is to develop a comprehensive model with the capability of modeling both a high Reynolds number and high magnetic…
(more)
▼ The main objective of this thesis is to develop a comprehensive model with the capability of modeling both a high Reynolds number and high magnetic Reynolds number turbulent flow for application to supersonic combustor. The development of this model can be divided
into three categories: one, the development of a self-consistent MHD numerical model capable of
modeling magnetic turbulence in high magnetic Reynolds number applications. Second, the development of a gas discharge model which models the interaction of externally applied fields in conductive medium. Third, the development of models necessary for studying supersonic combustion applications with plasma-assistance
such the extension of chemical kinetics models to extremely high temperature and non-equilibrium phenomenon.
Advisors/Committee Members: Menon Suresh (Committee Chair), Jagoda Jeff (Committee Co-Chair), Ruffin Stephen (Committee Member), Thorsten Stoesser (Committee Member), Walker Mitchell (Committee Member).
Subjects/Keywords: Scramjet; MHD; Turbulence; Supersonic flow; Plasma; Magnetohydrodynamics; Airplanes Scramjet engines; Reynolds number; Aerodynamics
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APA (6th Edition):
Miki, K. (2009). Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/26605
Chicago Manual of Style (16th Edition):
Miki, Kenji. “Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion.” 2009. Doctoral Dissertation, Georgia Tech. Accessed June 18, 2019.
http://hdl.handle.net/1853/26605.
MLA Handbook (7th Edition):
Miki, Kenji. “Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion.” 2009. Web. 18 Jun 2019.
Vancouver:
Miki K. Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion. [Internet] [Doctoral dissertation]. Georgia Tech; 2009. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1853/26605.
Council of Science Editors:
Miki K. Simulation of magnetohydrodynamics turbulence with application to plasma-assisted supersonic combustion. [Doctoral Dissertation]. Georgia Tech; 2009. Available from: http://hdl.handle.net/1853/26605
12.
Rodrigues, Luís.
Thermodynamic analysis and optimization of a scramjet engine with thermal management system.
Degree: 2010, RCAAP
URL: https://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3686
► Thermal management of the scramjet engine is one of the key issues of the challenges brought by the development of hypersonic airbreathing vehicles. A Closed…
(more)
▼ Thermal management of the
scramjet engine is one of the key issues of the challenges brought by the development of hypersonic airbreathing vehicles. A Closed Brayton Cycle thermal management system for a regenerative cooled
scramjet is introduced with the goal of reducing the hydrogen fuel flow for cooling.
Part of the heat absorbed from fuel is converted into other forms of energy to decrease the heat that must be taken away by hydrogen fuel. Reducing this heat increases the fuel heat sink (cooling capacity)
without requiring excess fuel for cooling and eliminating the need to search for a new coolant. The proposed thermal cycle reduces the fuel flow for cooling, and this way, the fuel on board assures the cooling requirements for the whole hypersonic vehicle. The basic concept and working principle are introduced:
a thermodynamic cycle analysis is performed to demonstrate the system performance gains of Closed Brayton Cycle (CBC) Thermal Management System (TMS) over the conventional system with regenerative
cooling. It was shown that the Closed Brayton Cycle Thermal Management Systems presents a high performance gain when compared to conventional regenerative cooling due to the reduction of fuel
flow for cooling and additional power output.
Advisors/Committee Members: Brójo, Francisco Miguel Ribeiro Proença.
Subjects/Keywords: Scramjet (motor) - Veículos hipersónicos; Arrefecimento regenerativo - Motor - Veículo hipersónico; Arrefecimento regenerativo - Veículo hipersónico; Gestão térmica - Scramjet (motor) - Veículos hipersónicos
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APA (6th Edition):
Rodrigues, L. (2010). Thermodynamic analysis and optimization of a scramjet engine with thermal management system. (Thesis). RCAAP. Retrieved from https://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3686
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rodrigues, Luís. “Thermodynamic analysis and optimization of a scramjet engine with thermal management system.” 2010. Thesis, RCAAP. Accessed June 18, 2019.
https://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3686.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rodrigues, Luís. “Thermodynamic analysis and optimization of a scramjet engine with thermal management system.” 2010. Web. 18 Jun 2019.
Vancouver:
Rodrigues L. Thermodynamic analysis and optimization of a scramjet engine with thermal management system. [Internet] [Thesis]. RCAAP; 2010. [cited 2019 Jun 18].
Available from: https://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3686.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rodrigues L. Thermodynamic analysis and optimization of a scramjet engine with thermal management system. [Thesis]. RCAAP; 2010. Available from: https://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3686
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Virginia Tech
13.
Prebola, John L. Jr.
Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion.
Degree: MS, Aerospace and Ocean Engineering, 1998, Virginia Tech
URL: http://hdl.handle.net/10919/36941
► Research was conducted at Virginia Tech on a high-pressure uncooled plasma torch to study torch operational characteristics with hydrocarbon feedstocks and to determine the feasibility…
(more)
▼ Research was conducted at Virginia Tech on a high-pressure uncooled plasma torch to study torch operational characteristics with hydrocarbon feedstocks and to determine the feasibility of using the torch as an igniter in
scramjet applications. Operational characteristics studied included electrical properties, such as arc stability, voltage-current characteristics and start/re-start capabilities, and mechanical properties, such as coking, electrode erosion and transient to steady-state torch body temperature trends. Possible use of the plasma torch as an igniter in high-speed combustion environments was investigated through the use of emission spectroscopy and a NASA chemical kinetics code.
All feedstocks tested; argon, methane, ethylene and propylene, were able to start. The voltage data indicated that there were two preferred operating modes, which were well defined for methane. For all gases, a higher current setting, on the order of 40 A, led to more stable torch operation. A low intensity, high frequency current applied to the torch, along with the primary DC current, resulted in virtual elimination of soot deposits on the anodes. Electrode erosion was found to multiply each time the complexity of the hydrocarbon was increased. Audio and high-speed visual analysis led to identification of 180 Hz plasma formation cycle, related to the three-phase power supply. The spectroscopic analysis aided in the identification of combustion enhancing radicals being produced by the torch, and results of the chemical kinetics analysis verified combustion enhancement and radical production through the use of a basic plasma model. Overall, the results of this study indicate that the plasma torch is a promising source for
scramjet ignition, and further study is warranted.
Advisors/Committee Members: Schetz, Joseph A. (committeechair), O'Brien, Walter F. Jr. (committee member), Yates, Charlie L. (committee member).
Subjects/Keywords: plasma torch; hydrocarbon feedstocks; scramjet; scramjet combustion
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APA (6th Edition):
Prebola, J. L. J. (1998). Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/36941
Chicago Manual of Style (16th Edition):
Prebola, John L Jr. “Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion.” 1998. Masters Thesis, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/36941.
MLA Handbook (7th Edition):
Prebola, John L Jr. “Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion.” 1998. Web. 18 Jun 2019.
Vancouver:
Prebola JLJ. Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion. [Internet] [Masters thesis]. Virginia Tech; 1998. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/36941.
Council of Science Editors:
Prebola JLJ. Performance of a Plasma Torch with Hydrocarbon Feedstocks for Use in Scramjet Combustion. [Masters Thesis]. Virginia Tech; 1998. Available from: http://hdl.handle.net/10919/36941
University of Kansas
14.
Tourani, Chandraprakash Chandra.
COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS.
Degree: MS, Aerospace Engineering, 2011, University of Kansas
URL: http://hdl.handle.net/1808/7635
► 1-D simulations based on the quasi-one-dimensional equations of fluid motion plus an ignition delay model and 2-D numerical simulations based on Reynolds-Averaged Navier-Stokes (RANS) equations…
(more)
▼ 1-D simulations based on the quasi-one-dimensional equations of fluid motion plus an ignition delay model and 2-D numerical simulations based on Reynolds-Averaged Navier-Stokes (RANS) equations have been performed for two different
scramjet combustors. The combustor configurations at DLR and NASA's SCHOLAR Supersonic Combustor have been used as test cases for the 1-D and 2-D simulations. Comparisons between the published 3-D computational and experimental results and quasi-one-dimensional and 2-D simulations have been performed. The quasi-one dimensional modeling of NASA's SCHOLAR supersonic combustor captures the trends in Mach number, static pressure and static temperature for both cold flow and combustion case. The comparison with experimental result for combustion case reveals a close agreement with the pressure peak and the presence of an ignition delay. Thus, 1-D simulation very closely predicts the flow evolution within the combustor. On the other hand, for DLR supersonic combustor, due to the lack of oblique wave (i.e. shock waves and expansion waves) and shear dominated viscous flow simulation, 1-D model severely fails to predict the trend followed by the experimental result along the centerline of the combustor. However, the 1-D model is able to match the overall flow velocity achieved within the combustor downstream of the wedge at approximately six wedge chord lengths.
Advisors/Committee Members: Farokhi, Saeed (advisor), Taghavi, Ray (cmtemember), Keshmiri, Shahriar (cmtemember).
Subjects/Keywords: Aerospace engineering; Air-breathing propulsion; Combustor; Hypersonic; Quasi one-dimensional; Scramjet
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Export
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Manager
APA (6th Edition):
Tourani, C. C. (2011). COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS. (Masters Thesis). University of Kansas. Retrieved from http://hdl.handle.net/1808/7635
Chicago Manual of Style (16th Edition):
Tourani, Chandraprakash Chandra. “COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS.” 2011. Masters Thesis, University of Kansas. Accessed June 18, 2019.
http://hdl.handle.net/1808/7635.
MLA Handbook (7th Edition):
Tourani, Chandraprakash Chandra. “COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS.” 2011. Web. 18 Jun 2019.
Vancouver:
Tourani CC. COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS. [Internet] [Masters thesis]. University of Kansas; 2011. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1808/7635.
Council of Science Editors:
Tourani CC. COMPUTATIONAL SIMULATION OF SCRAMJET COMBUSTORS - A COMPARISON BETWEEN QUASI-ONE DIMENSIONAL AND 2-D NUMERICAL SIMULATIONS. [Masters Thesis]. University of Kansas; 2011. Available from: http://hdl.handle.net/1808/7635
University of Kansas
15.
Hwang, Seung-Jae.
Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar.
Degree: PhD, Aerospace Engineering, 2011, University of Kansas
URL: http://hdl.handle.net/1808/8080
► Numerical simulations of the scramjet combustor by using the commercial CFD code Fluent with the coupled implicit method with second-order accurate discretization have been obtained…
(more)
▼ Numerical simulations of the
scramjet combustor by using the commercial CFD code Fluent with the coupled implicit method with second-order accurate discretization have been obtained for the reacting flows with the parallel fuel injection (ramp injection) and normal fuel injection (wall injection) schemes. Incorporated in the
scramjet combustors are delta tabs and suction collars of two types as means of mixing enhancement. The main mechanism of the tabs and suction collars for mixing enhancement is the generation of streamwise vorticity and providing outstanding flameholding capability along with the induced global instability of the shear layer. The idea has been previously recommended for mixing enhancement of the
scramjet combustor, but no experimental or computational data on the combustor performance has been reported, yet. The finite rate reaction model is used for the species transport model that only considers four species, H2, O2, H2O and N2. Vitiated air (mass fraction of O2, H2O, and N2 being 0.198, 0.139, and 0.663, respectively) enters the combustor at Mach number of 2.5 at a stagnation temperature and pressure of 1500 K and 101,325 Pa, respectively. The equivalence ratio is fixed at 0.45 in the present study. An optimization study of the combinations of the tabs and suction collars has been performed. Uninstalled thrust force for the optimal combination which was composed of the relieved ramp, 4 delta tabs, suction collar type I and 4 delta tabs in the fuel inlet scheme produced an additional 73% increase in thrust with only an additional 3.37% loss of the total pressure compared to the ramp injection alone, i.e., the baseline case. The numerical results clearly indicate that the fuel injection schemes investigated in the present study are more efficient than a strut or multi-staged strut and wall injection scheme.
Advisors/Committee Members: Farokhi, Saeed (advisor), Taghavi, Ray (cmtemember), Barrett-Gonzalez, Ron (cmtemember), Keshmiri, Shahriar (cmtemember), Huang, Weizhang (cmtemember).
Subjects/Keywords: Aerospace engineering; Combustor; Enhanced; Mixing; Scramjet; Suction collar; Tabs
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Export
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APA (6th Edition):
Hwang, S. (2011). Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/8080
Chicago Manual of Style (16th Edition):
Hwang, Seung-Jae. “Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar.” 2011. Doctoral Dissertation, University of Kansas. Accessed June 18, 2019.
http://hdl.handle.net/1808/8080.
MLA Handbook (7th Edition):
Hwang, Seung-Jae. “Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar.” 2011. Web. 18 Jun 2019.
Vancouver:
Hwang S. Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar. [Internet] [Doctoral dissertation]. University of Kansas; 2011. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1808/8080.
Council of Science Editors:
Hwang S. Numerical Simulation of Enhanced Mixing in Scramjet Combustor Using Ramp, Tabs and Suction Collar. [Doctoral Dissertation]. University of Kansas; 2011. Available from: http://hdl.handle.net/1808/8080
University of Kansas
16.
Smith, Leslie Ann.
The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber.
Degree: PhD, Aerospace Engineering, 2015, University of Kansas
URL: http://hdl.handle.net/1808/19415
► One of the greatest problems that scramjet research faces is fuel air mixing. The residence time for a scramjet engine, or the time it takes…
(more)
▼ One of the greatest problems that
scramjet research faces is fuel air mixing. The residence time for a
scramjet engine, or the time it takes for a volume of air to completely pass through the engine, is on the order of 0.1 ms. In that extremely short period of time fuel must be injected and fully mirco-mixed at stoichiometric ratios with the combustion chamber airflow. The fuel-air mixture must then be combusted and expanded through the nozzle to produce thrust. The goal of this research is to develop a new more efficient method of fuel air mixing within a
scramjet combustion chamber. A possible way to speed up the mixing process of parallel injection without incurring the total pressure losses that would occur in normal injection is to inject the fuel from the rear side of a backward facing step. Backward facing steps in supersonic flow produce a Prandtl-Meyer expansion fan followed by a shear layer. The instabilities in this shear layer have dominant resonant frequencies. It is believed that if fuel is injected in pulses that impinge on the shear layer at these dominant resonant frequencies that the shear layer will resonate. When the shear layer resonates the vortices that form in the shear layer will grow in magnitude, thus mixing the injected fuel with the air. To test this hypothesis a new test section was designed and built that features a one inch step under which an injector can be housed. This new test section was installed in the supersonic facility at the University of Kansas. Two injectors were also designed that each feature a face plate, one with eight injection ports arranged in a ring and one with 5 injection ports. Between the face plate and a back plate there is a cavity that houses a rotating valve that is powered by a pneumatic motor. Five valves were built: one with 8 teeth, one with 16 teeth, one with 5 teeth that are the same size as the gaps between the teeth, one with 5 teeth where the teeth are 50% larger than the gaps, and one with 5 teeth where the teeth are 50% smaller than the gaps. The 8 tooth valve and 16 tooth valve where used with the 8 port injector face plate. The 5 tooth valves were used with the 5 port injector face plate. As the valve rotates the teeth block and unblock the injection ports injecting carbon dioxide gas into the test section. The 8 port injector was tested over a range of frequencies from 1.6 kHz to 10.0 kHz. The 5 port injector was tested for each valve over a range of frequencies from 1.0 kHz to 4.0 kHz. Static pressure data was taken along the upper and lower walls of the test section by means of an array of pressure sensors. The pressure data from the test section was compared to results generated using a three dimensional CFD simulation of the test section. Overall the pressure data on the lower wall agreed reasonably well with the CFD simulation. The vorticity and turbulence contours generated by the STAR-CCM+ simulation suggest that as a pulse is injected into the test section from the step it causes the shear layer to curve outward near the point of…
Advisors/Committee Members: Farokhi, Saeed (advisor), Barrett, Ron (cmtemember), Taghavi, Ray (cmtemember), Yimer, Bedru (cmtemember), Keshmiri, Shawn (cmtemember).
Subjects/Keywords: Aerospace engineering; Injector; Micro-mixing; Pulsed Injection; Scramjet; Shear Layer
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APA (6th Edition):
Smith, L. A. (2015). The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/19415
Chicago Manual of Style (16th Edition):
Smith, Leslie Ann. “The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber.” 2015. Doctoral Dissertation, University of Kansas. Accessed June 18, 2019.
http://hdl.handle.net/1808/19415.
MLA Handbook (7th Edition):
Smith, Leslie Ann. “The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber.” 2015. Web. 18 Jun 2019.
Vancouver:
Smith LA. The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber. [Internet] [Doctoral dissertation]. University of Kansas; 2015. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1808/19415.
Council of Science Editors:
Smith LA. The Effect of Pulsed Injection on Shear Layer Dynamics in a Scramjet Combustion Chamber. [Doctoral Dissertation]. University of Kansas; 2015. Available from: http://hdl.handle.net/1808/19415
University of Kansas
17.
Flesberg, Sonja.
Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl.
Degree: PhD, Aerospace Engineering, 2015, University of Kansas
URL: http://hdl.handle.net/1808/19380
► The scramjet engine has proven to be a viable means of powering a hypersonic vehicle, especially after successful flights of the X-51 WaveRider and various…
(more)
▼ The
scramjet engine has proven to be a viable means of powering a hypersonic vehicle, especially after successful flights of the X-51 WaveRider and various Hy-SHOT test vehicles. The major challenge associated with operating a
scramjet engine is the short residence time of the fuel and oxidizer in the combustor. The fuel and oxidizer have only milliseconds to mix, ignite and combust in the combustion chamber. Combustion cannot occur until the fuel and oxidizer are mixed on a molecular level. Therefore the improvement of mixing is of utmost interest since this can increase combustion efficiency. This study investigated mixing enhancement of fuel and oxidizer within the combustion chamber of a
scramjet by introducing swirl to the fuel jet. The investigation was accomplished with numerical simulations using STAR-CCM+ computational fluid dynamic software. The geometry of the University of Virginia Supersonic Combustion Facility was used to model the isolator, combustor and nozzle of a
scramjet engine for simulation purposes. Experimental data from previous research at the facility was used to verify the simulation model before investigating the effect of fuel jet swirl on mixing. The model used coaxial fuel jet with a swirling annular jet. Single coaxial fuel jet and dual coaxial fuel jet configurations were simulated for the investigation. The coaxial fuel jets were modelled with a swirling annular jet and non-swirling core jet. Numerical analysis showed that fuel jet swirl not only increased mixing and entrainment of the fuel with the oxidizer but the mixing occurred further upstream than without fuel jet swirl. The burning efficiency was calculated for the all the configurations. An increase in burning efficiency indicated an increase in the mixing of H2 with O2. In the case of the single fuel jet models, the maximum burning efficiency increase due to fuel injection jet swirl was 23.3%. The research also investigated the possibility that interaction between two swirling jets would produce increased mixing and to study how the distance between the two fuel injector exits would affect mixing. Three swirl patterns were investigated: 1) the first swirl pattern as viewed by an observer looking downstream had the right fuel annular jet swirling counter clockwise and the left fuel annular jet swirling clockwise, 2) the second swirl pattern as viewed by an observer looking downstream had the right fuel jet swirling clockwise and the left fuel jet swirling counter clockwise, 3) the third swirl pattern as viewed by an observer looking downstream had both the right and left fuel jet swirling in the same clockwise direction. Each one of the swirl patterns were simulated with the distances between the center points of the fuel jets modelled 3, 4, and 5 times the fuel injector radius. The swirl pattern that produced the greatest increase in burning efficiency differed according to the fuel injector spacing. The maximum increase in burning efficiency compared to the corresponding non-swirling two jet baseline case was 24.6% and was…
Advisors/Committee Members: Taghavi, Ray (advisor), Farokhi, Saeed (advisor), Taghavi, Ray (cmtemember), Farokhi, Saeed (cmtemember), Hale, Richard (cmtemember), Barrett, Ronald (cmtemember), Yimer, Bedru (cmtemember).
Subjects/Keywords: Aerospace engineering; fuel jet injection swirl; mixing enhancement; scramjet combustion
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APA ·
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APA (6th Edition):
Flesberg, S. (2015). Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/19380
Chicago Manual of Style (16th Edition):
Flesberg, Sonja. “Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl.” 2015. Doctoral Dissertation, University of Kansas. Accessed June 18, 2019.
http://hdl.handle.net/1808/19380.
MLA Handbook (7th Edition):
Flesberg, Sonja. “Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl.” 2015. Web. 18 Jun 2019.
Vancouver:
Flesberg S. Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl. [Internet] [Doctoral dissertation]. University of Kansas; 2015. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1808/19380.
Council of Science Editors:
Flesberg S. Mixing Enhancement in a Scramjet Combustor Using Fuel Jet Injection Swirl. [Doctoral Dissertation]. University of Kansas; 2015. Available from: http://hdl.handle.net/1808/19380
University of Cincinnati
18.
Barone, Dominic L.
Investigation of TDLAS Measurements in a Scramjet
Engine.
Degree: MS, Engineering : Aerospace Engineering, 2010, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277130335
► An investigation of the viability of tunable diode laser absorption spectroscopy for use as a flow measurement device in a scramjet engine was completed.…
(more)
▼ An investigation of the viability of tunable
diode laser absorption spectroscopy for use as a flow measurement
device in a
scramjet engine was completed. First, the effects on
TDLAS measurements across a temperature jump that is common in
scramjet combustor flow-paths was studied using a flat flame burner
designed with four independently fueled quadrants. Rigorous
thermocouple mapping of the burner was performed and a discussion
of multi-thermocouple radiation correction techniques is presented.
The fundamental mass capture measurements
(temperature, water number density, pressure, and velocity) were
then made in the isolator section of a direct-connect
scramjet
engine and compared to a
scramjet performance analysis code.
Post-combustion measurements (temperature and water number density)
were measured in the exhaust section of the model engine. The
results of the measurements and an in-depth discussion of analysis
routines used in the processing of raw absorption measurements is
presented.
Advisors/Committee Members: Jeng, San-Mou (Committee Chair).
Subjects/Keywords: Aerospace Materials; Tunable Diode Laser; Absorption; Spectroscopy; TDLAS; Scramjet
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APA (6th Edition):
Barone, D. L. (2010). Investigation of TDLAS Measurements in a Scramjet
Engine. (Masters Thesis). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277130335
Chicago Manual of Style (16th Edition):
Barone, Dominic L. “Investigation of TDLAS Measurements in a Scramjet
Engine.” 2010. Masters Thesis, University of Cincinnati. Accessed June 18, 2019.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277130335.
MLA Handbook (7th Edition):
Barone, Dominic L. “Investigation of TDLAS Measurements in a Scramjet
Engine.” 2010. Web. 18 Jun 2019.
Vancouver:
Barone DL. Investigation of TDLAS Measurements in a Scramjet
Engine. [Internet] [Masters thesis]. University of Cincinnati; 2010. [cited 2019 Jun 18].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277130335.
Council of Science Editors:
Barone DL. Investigation of TDLAS Measurements in a Scramjet
Engine. [Masters Thesis]. University of Cincinnati; 2010. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277130335
Purdue University
19.
Williams, Joseph.
Trajectory optimization using indirect methods and parametric scramjet cycle analysis.
Degree: MSin Aeronautics and Astronautics, Aeronautics and Astronautics, 2016, Purdue University
URL: https://docs.lib.purdue.edu/open_access_theses/908
► This study investigates the solution of time sensitive regional strike trajectories for hypersonic missiles. This minimum time trajectory is suspected to be best performed…
(more)
▼ This study investigates the solution of time sensitive regional strike trajectories for hypersonic missiles. This minimum time trajectory is suspected to be best performed by
scramjet powered hypersonic missiles which creates strong coupled interaction between the flight dynamics and the performance of the engine. Comprehensive engine models are necessary to gain better insight into
scramjet propulsion. Separately, robust and comprehensive trajectory analysis provides references for vehicles to fly along. However, additional observation and understanding is obtained by integrating the propulsion model inside the trajectory framework. Going beyond curve fitted thrusting models, an integrated
scramjet cycle analysis offers rapid trade studies on engine parameters and enables the identification of the most significant and optimal engine parameters for the mission as a whole. Regularization of bang-bang control problems by use of the Epsilon-Trig regularization method has created the possibility to preserve the original equations of motion while still solving these problems through indirect methods. Indirect methods incorporate mathematical information from the optimal control problem to provide high quality, integrated solutions. The minimum time optimal trajectory of a rocket propelled missile is compared to that of a
scramjet powered missile to determine the advantages of
scramjet technology in this application.
Advisors/Committee Members: Michael J. Grant, Michael J. Grant, William Crossley, Stephen Heister.
Subjects/Keywords: Applied sciences; Indirect; Optimization; Powered; Regularization; Scramjet; Trajectory; Aerospace Engineering
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APA (6th Edition):
Williams, J. (2016). Trajectory optimization using indirect methods and parametric scramjet cycle analysis. (Thesis). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_theses/908
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Williams, Joseph. “Trajectory optimization using indirect methods and parametric scramjet cycle analysis.” 2016. Thesis, Purdue University. Accessed June 18, 2019.
https://docs.lib.purdue.edu/open_access_theses/908.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Williams, Joseph. “Trajectory optimization using indirect methods and parametric scramjet cycle analysis.” 2016. Web. 18 Jun 2019.
Vancouver:
Williams J. Trajectory optimization using indirect methods and parametric scramjet cycle analysis. [Internet] [Thesis]. Purdue University; 2016. [cited 2019 Jun 18].
Available from: https://docs.lib.purdue.edu/open_access_theses/908.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Williams J. Trajectory optimization using indirect methods and parametric scramjet cycle analysis. [Thesis]. Purdue University; 2016. Available from: https://docs.lib.purdue.edu/open_access_theses/908
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Toronto
20.
West, Jonathan Philip.
Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet.
Degree: 2011, University of Toronto
URL: http://hdl.handle.net/1807/29643
► A scramjet inlet was designed for use on a small scale, Mach six, ethylene-fuelled vehicle. The inlet used strut-based cantilevered fuel injectors and a well-defined…
(more)
▼ A scramjet inlet was designed for use on a small scale, Mach six, ethylene-fuelled vehicle. The inlet used strut-based cantilevered fuel injectors and a well-defined mixing duct to mix fuel prior to the combustor. Designed using theoretical and numerical analyses, the resulting inlet configuration consisted of a single body shock inlet with vertical fuel injector struts and four cantilevered injectors per strut side. This inlet was 80 cm long and 42 cm high. Numerical analysis of the vehicle was conducted with computational fluid dynamics by solving the Favre-Averaged Navier-Stokes equations; turbulence was simulated using the Wilcox k-ω model. Multispecies simulations in two and three dimensions were used to evaluate the design. Analysis of the simulated flow features, thrust potential and mixing efficiency demonstrated favourable vehicle performance. In particular, the inlet allowed for complete combustion when lean equivalence ratios of less than 0.7 were used.
MAST
Advisors/Committee Members: Sislian, Jean Pascal, Aerospace Science and Engineering.
Subjects/Keywords: scramjet; ethylene; hypersonic; fuel injection; fuel mixing; computational fluid dynamics; 0538
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APA (6th Edition):
West, J. P. (2011). Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/29643
Chicago Manual of Style (16th Edition):
West, Jonathan Philip. “Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet.” 2011. Masters Thesis, University of Toronto. Accessed June 18, 2019.
http://hdl.handle.net/1807/29643.
MLA Handbook (7th Edition):
West, Jonathan Philip. “Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet.” 2011. Web. 18 Jun 2019.
Vancouver:
West JP. Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet. [Internet] [Masters thesis]. University of Toronto; 2011. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1807/29643.
Council of Science Editors:
West JP. Numerical Analysis of Ethylene Injection in the Inlet of a Mach Six Scramjet. [Masters Thesis]. University of Toronto; 2011. Available from: http://hdl.handle.net/1807/29643
University of California – San Diego
21.
Sexton, Scott Michael.
Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers.
Degree: Engineering Sciences (Mechanical Engineering), 2017, University of California – San Diego
URL: http://www.escholarship.org/uc/item/70799141
► Combustion in scramjet engines is faced with the limitation of brief residence time in the combustion chamber, requiring fuel and preheated air streams to mix…
(more)
▼ Combustion in scramjet engines is faced with the limitation of brief residence time in the combustion chamber, requiring fuel and preheated air streams to mix and ignite in a matter of milliseconds. Accurate predictions of autoignition times are needed to design reliable supersonic combustion chambers. Most efforts in estimating non-premixed autoignition times have been de- voted to hydrogen-air mixtures. The present work addresses hydrocarbon-air combustion, which is of interest for future scramjet engines.Computation of ignition in supersonic flows requires adequate characterization of ignition ixchemistry and description of the flow, both of which are derived in this work. In particular, we have shown that activation energy asymptotics combined with a previously derived reduced chemical kinetic mechanism provides analytic predictions of autoignition times in homogeneous systems. Results are compared with data from shock tube experiments, and previous expressions which employ a fuel depletion criterion.Ignition in scramjet engines has a strong dependence on temperature, which is found by perturbing the chemically frozen mixing layer solution. The frozen solution is obtained here, accounting for effects of viscous dissipation between the fuel and air streams. We investigate variations of thermodynamic and transport properties, and compare these to simplified mixing layers which neglect these variations. Numerically integrating the mixing layer problem reveals a nonmonotonic temperature profile, with a peak occurring inside the shear layer for sufficiently high Mach numbers.These results will be essential in computation of ignition distances in supersonic combus- tion chambers.
Subjects/Keywords: Aerospace engineering; Mechanical engineering; analytic; combustion; hydrocarbon; ignition; scramjet; supersonic
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APA (6th Edition):
Sexton, S. M. (2017). Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/70799141
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sexton, Scott Michael. “Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers.” 2017. Thesis, University of California – San Diego. Accessed June 18, 2019.
http://www.escholarship.org/uc/item/70799141.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sexton, Scott Michael. “Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers.” 2017. Web. 18 Jun 2019.
Vancouver:
Sexton SM. Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers. [Internet] [Thesis]. University of California – San Diego; 2017. [cited 2019 Jun 18].
Available from: http://www.escholarship.org/uc/item/70799141.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sexton SM. Progress Toward Analytic Predictions of Supersonic Hydrocarbon-Air Combustion: Computation of Ignition Times and Supersonic Mixing Layers. [Thesis]. University of California – San Diego; 2017. Available from: http://www.escholarship.org/uc/item/70799141
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Oregon State University
22.
Nahorniak, Matthew T.
Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames.
Degree: MS, Mechanical Engineering, 1996, Oregon State University
URL: http://hdl.handle.net/1957/34208
► The purpose of this research was to determine if it is feasible to apply Lorentz mixing to supersonic diffusion flames, such as those found in…
(more)
▼ The purpose of this research was to determine if it is feasible to apply Lorentz
mixing to supersonic diffusion flames, such as those found in
SCRAMjet engines. The
combustion rate in supersonic diffusion flames is limited by the rate at which air and fuel
mix. Lorentz mixing increases turbulence within a flow, which increases the rate at which
species mix and thus increases the rate of combustion.
In order to determine the feasibility of Lorentz mixing for this application, a two-dimensional model of supersonic reacting flow with the application of a Lorentz force has been examined numerically. The flow model includes the complete Navier-Stokes equations, the ideal gas law, and terms to account for diffusion of chemical species, heat release due to chemical reaction, change in species density due to chemical reaction, and the Lorentz forces applied during Lorentz mixing. In addition, the Baldwin-Lomax turbulence model is used to approximate turbulent transport properties.
A FORTRAN program using the MacCormack method, a commonly used computational fluid dynamics algorithm, was used to solve the governing equations. The accuracy of the program was verified by using the program to model flows with known solutions.
Results were obtained for flows with Lorentz forces applied over a series of power levels and frequencies. The results show significant increases in the rate of combustion
when Lorentz mixing is applied. The amount of power required to drive Lorentz mixing is small relative to the rate at which energy is released in the chemical reaction. An optimum frequency at which to apply Lorentz mixing was also found for the flow being considered.
The results of the current study show that Lorentz mixing looks promising for increasing combustion rates in supersonic reacting flows, and that future study is warranted. In particular, researchers attempting to improve combustion in
SCRAMjet engines may want to consider Lorentz mixing as a way to improve combustion.
Advisors/Committee Members: Pattee, Heidi A. (advisor).
Subjects/Keywords: Airplanes – Scramjet engines – Mathematical models
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APA (6th Edition):
Nahorniak, M. T. (1996). Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/34208
Chicago Manual of Style (16th Edition):
Nahorniak, Matthew T. “Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames.” 1996. Masters Thesis, Oregon State University. Accessed June 18, 2019.
http://hdl.handle.net/1957/34208.
MLA Handbook (7th Edition):
Nahorniak, Matthew T. “Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames.” 1996. Web. 18 Jun 2019.
Vancouver:
Nahorniak MT. Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames. [Internet] [Masters thesis]. Oregon State University; 1996. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/1957/34208.
Council of Science Editors:
Nahorniak MT. Feasibility of Lorentz mixing to enhance combustion in supersonic diffusion flames. [Masters Thesis]. Oregon State University; 1996. Available from: http://hdl.handle.net/1957/34208
Virginia Tech
23.
Markell, Kyle Charles.
Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts.
Degree: MS, Mechanical Engineering, 2005, Virginia Tech
URL: http://hdl.handle.net/10919/31256
► This thesis work presents detailed results of the application of exergy-based methods to highly dynamic, integrated aerospace systems such as hypersonic vehicle concepts. In particular,…
(more)
▼ This thesis work presents detailed results of the application of exergy-based methods to highly dynamic, integrated aerospace systems such as hypersonic vehicle concepts. In particular, an exergy-based methodology is compared to a more traditional based measure by applying both to the synthesis/design and operational optimization of a hypersonic vehicle configuration comprised of an airframe sub-system and a propulsion sub-system consisting of inlet, combustor, and nozzle components. A number of key design and operational decision variables are identified as those which govern the hypersonic vehicle flow physics and thermodynamics and detailed one-dimensional models of each component and sub-system are developed. Rates of exergy loss as well as exergy destruction resulting from irreversible loss mechanisms are determined in each of the hypersonic vehicle sub-systems and their respective components.
Multiple optimizations are performed for both the propulsion sub-system only and for the entire hypersonic vehicle system for single mission segments and for a partial, three-segment mission. Three different objective functions are utilized in these optimizations with the specific goal of comparing exergy methods to a standard vehicle performance measure, namely, the vehicle overall efficiency. Results of these optimizations show that the exergy method presented here performs well when compared to the standard performance measure and, in a number of cases, leads to more optimal syntheses/designs in terms of the fuel mass flow rate required for a given task (e.g., for a fixed-thrust requirement or a given mission).
In addition to the various vehicle design optimizations, operational optimizations are conducted to examine the advantage if any of energy exchange to maintain shock-on-lip for both design and off-design conditions. Parametric studies of the hypersonic vehicle sub-systems and components are also conducted and provide further insights into the impacts that the design and operational decision variables and flow properties have on the rates of exergy destruction.
Advisors/Committee Members: von Spakovsky, Michael R. (committeechair), Moorhouse, David (committee member), Ellis, Michael W. (committee member), O'Brien, Walter F. Jr. (committee member).
Subjects/Keywords: scramjet; exergy; optimization; hypersonic's
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APA (6th Edition):
Markell, K. C. (2005). Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/31256
Chicago Manual of Style (16th Edition):
Markell, Kyle Charles. “Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts.” 2005. Masters Thesis, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/31256.
MLA Handbook (7th Edition):
Markell, Kyle Charles. “Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts.” 2005. Web. 18 Jun 2019.
Vancouver:
Markell KC. Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts. [Internet] [Masters thesis]. Virginia Tech; 2005. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/31256.
Council of Science Editors:
Markell KC. Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts. [Masters Thesis]. Virginia Tech; 2005. Available from: http://hdl.handle.net/10919/31256
Virginia Tech
24.
Rock, Christopher.
Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors.
Degree: PhD, Aerospace and Ocean Engineering, 2010, Virginia Tech
URL: http://hdl.handle.net/10919/77208
► A flush-wall injector model and a strut injector model representative of state of the art scramjet engine combustion chambers were experimentally studied in a cold-flow…
(more)
▼ A flush-wall injector model and a strut injector model representative of state of the art
scramjet engine combustion chambers were experimentally studied in a cold-flow (non-combusting) environment to determine their fuel-air mixing behavior under different operating conditions. The experiments were run at nominal freestream Mach numbers of 2 and 4, which simulates combustor conditions for nominal flight Mach numbers of 5 and 10. The flush-wall injector model consists of sixteen inclined, round, sonic injectors distributed around the wall of a circular duct. The strut injector model has sixteen inclined, round, sonic injectors distributed across four struts within a circular duct. The struts are slender, inclined at a low angle to minimize drag, and have two injectors on each side. The experiments investigated the effects of injectant molecular weight, freestream Mach number, and jet-to-freestream momentum flux ratio on the fuel-air mixing process. Helium, methane, and air injectants were studied to vary the injectant molecular weight over the range of 4-29. All of these experiments were performed to support the needs of an integrated experimental and computational research program, which has the goal of upgrading the turbulence models that are used for Computational Fluid Dynamics predictions of the flow inside a
scramjet combustor. The primary goals of this study were to use injector models that represent state of the art
scramjet engine combustion chambers to provide validation data to support the development of turbulence model upgrades and to add to the sparse database of mixing results in such configurations. The main experimental results showed that higher molecular weight injectants had approximately the same amount of penetration in the far field as lower molecular weight injectants at the same jet-to-freestream momentum flux ratio. Higher molecular weight injectants also demonstrated a mixing rate that was the same as or slower than lower molecular weight injectants depending on the flow conditions. A comparison of the experimental results for the two different injector models revealed that the flush-wall injector mixed significantly faster than the strut injector in all of the experimental cases.
Advisors/Committee Members: Schetz, Joseph A. (committeechair), Philen, Michael K. (committee member), O'Brien, Walter F. Jr. (committee member), Devenport, William J. (committee member).
Subjects/Keywords: Fuel Injection; Mixing; Hypersonic Propulsion; Supersonic Combustion; Scramjet
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APA (6th Edition):
Rock, C. (2010). Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/77208
Chicago Manual of Style (16th Edition):
Rock, Christopher. “Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors.” 2010. Doctoral Dissertation, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/77208.
MLA Handbook (7th Edition):
Rock, Christopher. “Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors.” 2010. Web. 18 Jun 2019.
Vancouver:
Rock C. Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors. [Internet] [Doctoral dissertation]. Virginia Tech; 2010. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/77208.
Council of Science Editors:
Rock C. Experimental Studies of Injector Array Configurations for Circular Scramjet Combustors. [Doctoral Dissertation]. Virginia Tech; 2010. Available from: http://hdl.handle.net/10919/77208
Virginia Tech
25.
Cox-Stouffer, Susan K. Jr.
Numerical Simulation of Injection and Mixing in Supersonic Flow.
Degree: PhD, Aerospace and Ocean Engineering, 1997, Virginia Tech
URL: http://hdl.handle.net/10919/29628
► A numerical investigation of the performance of two candidate designs for injection into supersonic flow, including a comparison of two renormalized group theory (RNG) based…
(more)
▼ A numerical investigation of the performance of two candidate designs for injection into supersonic flow, including a comparison of two renormalized group theory (RNG) based k-epsilon turbulence models with a more conventional k-epsilon model. The chosen designs were an unswept ramp injector with four injection ports and a novel nine-hole injector array. The objectives of the investigation were to provide reliable computational solutions to the flowfields in question using both RNG and standard k-epsilon turbulence models and to compare the solutions to experiment, thereby to judge the relative performance of the turbulence models. A second objective of the investigation was to use the computed data to provide design insights for the nine-hole injector array.
This investigation made use of GASP(tm) version 2.2, a commercial computational fluid dynamics code that was augmented by the addition of one RNG-based k-epsilon turbulence model derived by Zhou, et. al. and one variant of Zhou's model, which was derived by the author. Mesh sequencing studies were performed to measure solution quality, with the fine mesh for the injector array containing roughly one million grid nodes and the fine mesh for the ramp injector containing more than six million grid nodes. Results of these studies indicated that the injector-array solution was significantly under-resolved in the farfield, though the quality was better in the vicinity of the injector itself. The ramp-injector solution, while not perfectly grid-resolved, showed much better grid convergence in both the nearfield and farfield. Accordingly, comparison with experiment was better for the ramp injector than for the injector array. For both injectors, the differences between solutions generated with RNG-based k-epsilon and standard k-epsilon turbulence models were negligibly small.
Despite inadequate grid resolution in the farfield, the computational investigation of the nine-hole injector array did yield several important design insights. Particularly, the significance to mixing and losses of the placement of the outer injectors of the second and third rows was determined.
Advisors/Committee Members: Schetz, Joseph A. (committeechair), Grossman, Bernard M. (committee member), Ng, Wing Fai (committee member), Walters, Robert W. (committee member), Yates, Charlie L. (committee member).
Subjects/Keywords: scramjet; RNG; CFD; ramp injector
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APA (6th Edition):
Cox-Stouffer, S. K. J. (1997). Numerical Simulation of Injection and Mixing in Supersonic Flow. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/29628
Chicago Manual of Style (16th Edition):
Cox-Stouffer, Susan K Jr. “Numerical Simulation of Injection and Mixing in Supersonic Flow.” 1997. Doctoral Dissertation, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/29628.
MLA Handbook (7th Edition):
Cox-Stouffer, Susan K Jr. “Numerical Simulation of Injection and Mixing in Supersonic Flow.” 1997. Web. 18 Jun 2019.
Vancouver:
Cox-Stouffer SKJ. Numerical Simulation of Injection and Mixing in Supersonic Flow. [Internet] [Doctoral dissertation]. Virginia Tech; 1997. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/29628.
Council of Science Editors:
Cox-Stouffer SKJ. Numerical Simulation of Injection and Mixing in Supersonic Flow. [Doctoral Dissertation]. Virginia Tech; 1997. Available from: http://hdl.handle.net/10919/29628
Virginia Tech
26.
Brewer, Keith Merritt.
Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles.
Degree: MS, Mechanical Engineering, 2006, Virginia Tech
URL: http://hdl.handle.net/10919/32007
► Though the field of hypersonic vehicle design is thriving again, few studies to date demonstrate the technology through a mission in which multiple flight conditions…
(more)
▼ Though the field of hypersonic vehicle design is thriving again, few studies to date demonstrate the technology through a mission in which multiple flight conditions and constraints are encountered. This is likely due to the highly integrated and sensitive nature of hypersonic vehicle components. Consequently, a formal Mach 6 through Mach 10 flight envelope is explored which includes cruise, acceleration/climb, deceleration/descend and turn mission segments. An exergy approach to the vehicle synthesis/design, in which trade-offs between dissimilar technologies are observed, is proposed and measured against traditional methods of assessing highly integrated systems.
A quasi one-dimensional hypersonic vehicle system simulation program was constructed. Composed of two sub-systems, propulsion and airframe, mechanisms for loss are computed from such irreversible processes as shocks, friction, heat transfer, mixing, and incomplete combustion. The propulsion sub-system consists of inlet, combustor, and nozzle, while the airframe provides trim and force accounting measures. An energy addition mechanism, based on the potential of MHD technology, is utilized to maintain a shock-on-lip inlet operating condition. Thirteen decision variables (seven design and six operational) were chosen to govern the vehicle geometry and performance. A genetic algorithm was used to evaluate the optimal vehicle synthesis/design for three separate objective functions, i.e the optimizations involved the maximization of thrust efficiency, the minimization of fuel mass consumption, and the minimization of exergy destruction plus fuel exergy loss.
The principal results found the minimum fuel consumption and minimum exergy destruction measures equivalent, both meeting the constraints of the mission while using 11% less fuel than the thrust efficiency measure. Optimizing the vehicle for the single most constrained mission segment yielded a vehicle capable of flying the entire mission but with fuel consumption and exergy destruction plus fuel loss values greater than the above mentioned integrated vehicle solutions. In essence, the mission-level analysis provided much insight into the dynamics of mission-level hypersonic flight and demonstrated the usefulness of an exergy destruction minimization measure for highly integrated synthesis/design.
Advisors/Committee Members: von Spakovsky, Michael R. (committeechair), Ellis, Michael W. (committee member), O'Brien, Walter F. Jr. (committee member), Moorhouse, David (committee member).
Subjects/Keywords: exergy hypersonic optimization scramjet
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MLA ·
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Export
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APA (6th Edition):
Brewer, K. M. (2006). Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/32007
Chicago Manual of Style (16th Edition):
Brewer, Keith Merritt. “Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles.” 2006. Masters Thesis, Virginia Tech. Accessed June 18, 2019.
http://hdl.handle.net/10919/32007.
MLA Handbook (7th Edition):
Brewer, Keith Merritt. “Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles.” 2006. Web. 18 Jun 2019.
Vancouver:
Brewer KM. Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles. [Internet] [Masters thesis]. Virginia Tech; 2006. [cited 2019 Jun 18].
Available from: http://hdl.handle.net/10919/32007.
Council of Science Editors:
Brewer KM. Exergy Methods for the Mission-Level Analysis and Optimization of Generic Hypersonic Vehicles. [Masters Thesis]. Virginia Tech; 2006. Available from: http://hdl.handle.net/10919/32007
University of Cambridge
27.
Cocks, Peter.
Large eddy simulation of supersonic combustion with application to scramjet engines.
Degree: PhD, 2011, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/239344
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541905
► This work evaluates the capabilities of the RANS and LES techniques for the simulation of high speed reacting flows. These methods are used to gain…
(more)
▼ This work evaluates the capabilities of the RANS and LES techniques for the simulation of high speed reacting flows. These methods are used to gain further insight into the physics encountered and regimes present in supersonic combustion. The target application of this research is the scramjet engine, a propulsion system of great promise for efficient hypersonic flight. In order to conduct this work a new highly parallelised code, PULSAR, is developed. PULSAR is capable of simulating complex chemistry combustion in highly compressible flows, based on a second order upwind method to provide a monotonic solution in the presence of high gradient physics. Through the simulation of a non-reacting supersonic coaxial helium jet the RANS method is shown to be sensitive to constants involved in the modelling process. The LES technique is more computationally demanding but is shown to be much less sensitive to these model parameters. Nevertheless, LES results are shown to be sensitive to the nature of turbulence at the inflow; however this information can be experimentally obtained. The SCHOLAR test case is used to validate the reacting aspects of PULSAR. Comparing RANS results from laminar chemistry and assumed PDF combustion model simulations, the influence of turbulence-chemistry interactions in supersonic combustion is shown to be small. In the presence of reactions, the RANS results are sensitive to inflow turbulence, due to its influence on mixing. From complex chemistry simulations the combustion behaviour is evaluated to sit between the flamelet and distributed reaction regimes. LES results allow an evaluation of the physics involved, with a pair of coherent vortices identified as the dominant influence on mixing for the oblique wall fuel injection method. It is shown that inflow turbulence has a significant impact on the behaviour of these vortices and hence it is vital for turbulence intensities and length scales to be measured by experimentalists, in order for accurate simulations to be possible.
Subjects/Keywords: 620; Scramjet; Supersonic combustion; Assumed pdf combustion model; Large eddy simulation
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cocks, P. (2011). Large eddy simulation of supersonic combustion with application to scramjet engines. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/239344 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541905
Chicago Manual of Style (16th Edition):
Cocks, Peter. “Large eddy simulation of supersonic combustion with application to scramjet engines.” 2011. Doctoral Dissertation, University of Cambridge. Accessed June 18, 2019.
https://www.repository.cam.ac.uk/handle/1810/239344 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541905.
MLA Handbook (7th Edition):
Cocks, Peter. “Large eddy simulation of supersonic combustion with application to scramjet engines.” 2011. Web. 18 Jun 2019.
Vancouver:
Cocks P. Large eddy simulation of supersonic combustion with application to scramjet engines. [Internet] [Doctoral dissertation]. University of Cambridge; 2011. [cited 2019 Jun 18].
Available from: https://www.repository.cam.ac.uk/handle/1810/239344 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541905.
Council of Science Editors:
Cocks P. Large eddy simulation of supersonic combustion with application to scramjet engines. [Doctoral Dissertation]. University of Cambridge; 2011. Available from: https://www.repository.cam.ac.uk/handle/1810/239344 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541905
University of Cambridge
28.
Cocks, Peter.
Large eddy simulation of supersonic combustion with application to scramjet engines
.
Degree: 2011, University of Cambridge
URL: http://www.dspace.cam.ac.uk/handle/1810/239344
► This work evaluates the capabilities of the RANS and LES techniques for the simulation of high speed reacting flows. These methods are used to gain…
(more)
▼ This work evaluates the capabilities of the RANS and LES techniques for the simulation of high speed reacting flows. These methods are used to gain further insight into the physics encountered and regimes present in supersonic combustion. The target application of this research is the
scramjet engine, a propulsion system of great promise for efficient hypersonic flight. In order to conduct this work a new highly parallelised code, PULSAR, is developed. PULSAR is capable of simulating complex chemistry combustion in highly compressible flows, based on a second order upwind method to provide a monotonic solution in the presence of high gradient physics.
Through the simulation of a non-reacting supersonic coaxial helium jet the RANS method is shown to be sensitive to constants involved in the modelling process. The LES technique is more computationally demanding but is shown to be much less sensitive to these model parameters. Nevertheless, LES results are shown to be sensitive to the nature of turbulence at the inflow; however this information can be experimentally obtained.
The SCHOLAR test case is used to validate the reacting aspects of PULSAR. Comparing RANS results from laminar chemistry and assumed PDF combustion model simulations, the influence of turbulence-chemistry interactions in supersonic combustion is shown to be small. In the presence of reactions, the RANS results are sensitive to inflow turbulence, due to its influence on mixing. From complex chemistry simulations the combustion behaviour is evaluated to sit between the flamelet and distributed reaction regimes. LES results allow an evaluation of the physics involved, with a pair of coherent vortices identified as the dominant influence on mixing for the oblique wall fuel injection method. It is shown that inflow turbulence has a significant impact on the behaviour of these vortices and hence it is vital for turbulence intensities and length scales to be measured by experimentalists, in order for accurate simulations to be possible.
Advisors/Committee Members: Dawes, Bill (advisor), Cant, Stewart (advisor).
Subjects/Keywords: Scramjet;
Supersonic combustion;
Assumed pdf combustion model;
Large eddy simulation
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cocks, P. (2011). Large eddy simulation of supersonic combustion with application to scramjet engines
. (Thesis). University of Cambridge. Retrieved from http://www.dspace.cam.ac.uk/handle/1810/239344
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cocks, Peter. “Large eddy simulation of supersonic combustion with application to scramjet engines
.” 2011. Thesis, University of Cambridge. Accessed June 18, 2019.
http://www.dspace.cam.ac.uk/handle/1810/239344.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cocks, Peter. “Large eddy simulation of supersonic combustion with application to scramjet engines
.” 2011. Web. 18 Jun 2019.
Vancouver:
Cocks P. Large eddy simulation of supersonic combustion with application to scramjet engines
. [Internet] [Thesis]. University of Cambridge; 2011. [cited 2019 Jun 18].
Available from: http://www.dspace.cam.ac.uk/handle/1810/239344.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cocks P. Large eddy simulation of supersonic combustion with application to scramjet engines
. [Thesis]. University of Cambridge; 2011. Available from: http://www.dspace.cam.ac.uk/handle/1810/239344
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Iowa State University
29.
Hagen, Wyatt.
Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets.
Degree: 2017, Iowa State University
URL: https://lib.dr.iastate.edu/etd/16718
► Liquid jets in crossflow are used in a variety of fuel injection systems. Of particular interest in this work is the injection of liquid fuel…
(more)
▼ Liquid jets in crossflow are used in a variety of fuel injection systems. Of particular interest in this work is the injection of liquid fuel into supersonic crossflow at scramjet startup conditions. Due to the short residence times of fuel in the combustor, it is imperative to efficiently and rapidly atomize and mix the fuel. Experiments often have limited ability to observe all of the wide range of scales and complicated liquid structures present in these conditions. Numerical simulations can provide additional insights into these complex flows. In this work, a numerical approach for the solution of compressible multi-component flows with capillary effects is presented along with additions to enable the solution of large computational problems. The approach is then validated against a non-turbulent round jet in subsonic crossflow. Comparisons to jet trajectory, column breakup location, and instability wavelengths are completed. A liquid jet in supersonic crossflow is simulated and the effects of a turbulence in the jet inflow are investigated. The jet trajectory is compared against experimental results. Although differences between the experimental results and numerical simulations are observed, the results suggest jet inflow turbulence can impact the atomization process in supersonic crossflow conditions and quantification of inflow conditions is important.
Subjects/Keywords: Atomization; Computational fluid dynamics; Liquid jet; Scramjet; Aerospace Engineering
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APA ·
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MLA ·
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Export
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Manager
APA (6th Edition):
Hagen, W. (2017). Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/16718
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hagen, Wyatt. “Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets.” 2017. Thesis, Iowa State University. Accessed June 18, 2019.
https://lib.dr.iastate.edu/etd/16718.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hagen, Wyatt. “Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets.” 2017. Web. 18 Jun 2019.
Vancouver:
Hagen W. Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets. [Internet] [Thesis]. Iowa State University; 2017. [cited 2019 Jun 18].
Available from: https://lib.dr.iastate.edu/etd/16718.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hagen W. Numerical modeling of liquid jets in crossflow with applications to supersonic combustion ramjets. [Thesis]. Iowa State University; 2017. Available from: https://lib.dr.iastate.edu/etd/16718
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Wright State University
30.
McGillivray, Nathan T.
Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design.
Degree: MSME, Mechanical Engineering, 2018, Wright State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=wright1536311445147862
► Various aspects of hypersonic vehicles are being rapidly explored for improved functionality. One of the main areas of consideration is the fueling of a Supersonic…
(more)
▼ Various aspects of hypersonic vehicles are being
rapidly explored for improved functionality. One of the main areas
of consideration is the fueling of a Supersonic Combusting Ramjet
(
scramjet) engine. Using Computational Fluid Dynamics (CFD),
computer simulations can be performed to analyze the flow physics
of a
scramjet. In this research, an optimization code, Dakota, is
integrated with the CFD to optimize a set of parameters to maximum
thrust. In this study, the fuel injection and combustion is
replaced with heat sources. This simplification greatly reduces the
computational requirements. Additionally, the 3D geometry is
reduced to an axisymmetric 2D geometry because three dimension
effects like mixing and combustion are not being modeled. With this
simplified model, the optimization and CFD algorithm is executed to
find the heat addition for maximum thrust. Different optimization
methods have been explored to reduce computational times. A genetic
algorithm was selected because of its robust abilities.
Additionally, a sampling algorithm was selected because of its
abilities to explore the whole design space. Furthermore, the
sampling method enables additional studies, such as sensitivity
studies, to be completed. In addition to optimization studies,
calibration studies are performed to obtain the heat source values
that correspond to a given experimental wall pressure distribution.
Knowledge of the optimized heat distribution will assist in the
optimization of fueling splits and injector locations for a more
detailed combustion investigation in which similar optimization
techniques can be applied.
Advisors/Committee Members: Wolff, Mitch (Advisor).
Subjects/Keywords: Aerospace Engineering; Mechanical Engineering; CFD; optimization; scramjet; hypersonic; DAKOTA; optimization routine
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McGillivray, N. T. (2018). Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design. (Masters Thesis). Wright State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=wright1536311445147862
Chicago Manual of Style (16th Edition):
McGillivray, Nathan T. “Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design.” 2018. Masters Thesis, Wright State University. Accessed June 18, 2019.
http://rave.ohiolink.edu/etdc/view?acc_num=wright1536311445147862.
MLA Handbook (7th Edition):
McGillivray, Nathan T. “Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design.” 2018. Web. 18 Jun 2019.
Vancouver:
McGillivray NT. Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design. [Internet] [Masters thesis]. Wright State University; 2018. [cited 2019 Jun 18].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1536311445147862.
Council of Science Editors:
McGillivray NT. Coupling Computational Fluid Dynamics Analysis and
Optimization Techniques for Scramjet Engine Design. [Masters Thesis]. Wright State University; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1536311445147862
◁ [1] [2] [3] [4] ▶
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Open Access Theses and Dissertations