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Delft University of Technology

1. Kinderman, Hendrik Wisse (author). The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:b5eaa808-6067-46a5-8d45-0e14d18ceeef

This research project aims at obtaining a better understanding of vertically translating the wing and the related wing-body interference effects on the drag and sonic boom. Computational Fluid Dynamics (CFD) analysis using the Euler equations has been used to evaluate an airplane with different vertical wing placements at a lift coefficient of 0.15 at a Mach-number of 1.6 and also in zero-lift conditions. Pressure distributions, drag forces and pressure signatures have been calculated in order to assess the performance in terms of wave drag and sonic booms. These results have been analysed to find out why certain effects are happening for these configurations. The low wing configuration has the highest lift-to-drag ratio due to interference on the upper wing surface close to the fuselage. The lift-to-drag ratio for CL = 0.15 is found to be 4.79% higher compared to the worst performing configuration, the high wing configuration. Due to the local geometry of the low wing configuration it is possible to cre- ate additional suction on the upper wing surface, which positively affects the performance. Pressure signatures are extracted at 1 body-length distance (70푚) from the aircraft for several azimuth angles. These distributions show that the low wing configuration also has the lowest impulse and maximum overpressure. The higher wing configurations show an extra peak in overpressure emanating from the trailing end of the wing, which is created due to interference effects. Below the wing surface there is a large volume of the fuselage, while it is absent for the low wing configuration. Therefore the higher wing configurations show an extra peak in the pressure signature. Next to this discovery, an analysis is presented to relate the geometry of the configurations to the wave drag by assessing the cross-sectional area distribution using different intersection methods. These methods are compared with other methods found in the literature. Two methods which use a single Mach-cone have been analysed, as well as a method incorporating a forward and a backward pointed Mach-cone. One method translates a Mach-cone vertically to align the vertex of the Mach-cone with the centroid of the intersection with the aircraft. This gives an x,z-position which can be used to adjust the area distribution. The drag for the methods using a single Mach-cone was overestimated by a factor of 2, but after multiplying these results by a factor of / the results for the heigh-weighted Mach-cone method approached the wave drag results from CFD within 5%. The double Mach-cone method showed an even better agreement with less variation, while no multiplication factor was applied. A further analysis has taken place to find out why some methods that incorporate a single Mach- cone to evaluate the cross-sectional area to calculate the wave drag, overestimate the drag by a factor of 2. It is found that these methods do not overestimate the drag for a simple shape, such as a Sears- Haack body. The methods simply overestimate the cross-sectional area,…
*Advisors/Committee Members: Schrijer, F.F.J. (mentor), Delft University of Technology (degree granting institution).*

Subjects/Keywords: sonic boom; vertical wing placement; wave drag; drag; supersonic; pressure signature; lift; zero-lift; area ruling; area rule; Mach; cone

Record Details Similar Records

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^{th} Edition):

Kinderman, H. W. (. (2017). The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:b5eaa808-6067-46a5-8d45-0e14d18ceeef

Chicago Manual of Style (16^{th} Edition):

Kinderman, Hendrik Wisse (author). “The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds.” 2017. Masters Thesis, Delft University of Technology. Accessed April 20, 2021. http://resolver.tudelft.nl/uuid:b5eaa808-6067-46a5-8d45-0e14d18ceeef.

MLA Handbook (7^{th} Edition):

Kinderman, Hendrik Wisse (author). “The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds.” 2017. Web. 20 Apr 2021.

Vancouver:

Kinderman HW(. The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Apr 20]. Available from: http://resolver.tudelft.nl/uuid:b5eaa808-6067-46a5-8d45-0e14d18ceeef.

Council of Science Editors:

Kinderman HW(. The impact of vertical wing placement on the wave drag and sonic-boom performance at supersonic speeds. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:b5eaa808-6067-46a5-8d45-0e14d18ceeef

2.
Bergman, David.
Modelling & implementation of Aerodynamic *Zero*-*lift* Drag into ADAPDT.

Degree: Design and Engineering, 2009, Mälardalen University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7459

The objective of this thesis work was to construct and implement an algorithm into the programADAPDT to calculate the zero-lift drag profile for defined aircraft geometries. ADAPDT, shortfor AeroDynamic Analysis and Preliminary Design Tool, is a program that calculates forces andmoments about a flat plate geometry based on potential flow theory. Zero-lift drag will becalculated by means of different hand-book methods found suitable for the objective andapplicable to the geometry definition that ADAPDT utilizes. Drag has two main sources of origin: friction and pressure distribution, all drag acting on theaircraft can be traced back to one of these two physical phenomena. In aviation drag is dividedinto induced drag that depends on the lift produced and zero-lift drag that depends on the geometry of the aircraft. How reliable and accurate the zero-lift drag computations are depends on the geometry data thatcan be extracted and used. ADAPDT‟s geometry definition is limited to flat plate geometrieshowever although simple it has the potential to provide a huge amount of data and also delivergood results for the intended use. The flat plate representation of the geometry proved to beleast sufficient for the body while wing elements could be described with much more accuracy. Different empirical hand-book methods were used to create the zero-lift drag algorithm. Whenchoosing equations and formulas, great care had to be taken as to what input was required sothat ADAPDT could provide the corresponding output. At the same time the equations shouldnot be so basic that level of accuracy would be compromised beyond what should be expectedfrom the intended use. Finally, four well known aircraft configurations, with available zero-lift drag data, weremodeled with ADAPDT‟s flat plate geometry in order to validate, verify and evaluate the zeroliftdrag algorithm‟s magnitude of reliability. The results for conventional aircraft geometriesprovided a relative error within 0-15 % of the reference data given in the speed range of zero toMach 1.2. While for an aircraft with more complicated body geometry the error could go up to40 % in the same speed regime. But even though the limited geometry is grounds foruncertainties the final product provides ADAPDT with very good zero-lift drag estimationcapability earlier not available. A capability that overtime as ADAPDT continues to evolve hasthe potential to further develop in terms of improved accuracy.

Målet med detta examensarbete var att skapa och implementera en algoritm som införmöjligheten att beräkna nollmotstånd för givna flygplansgeometrier i programmet ADAPDT.ADAPDT, kort för AeroDynamic Analysis and Preliminary Design Tool, är ett program som,baserat på potential strömnings teori, beräknar krafter och moment på en geometri uppbyggd avplana plattor. Nollmotståndet kommer att baseras en kombination av handboksmetoder somfunnits lämpliga och applicerbara på geometridefinitionen given i ADAPDT. Motstånd har sitt ursprung i två fysikaliska…

Subjects/Keywords: drag; zero-lift drag; aerodynamics; nollmotsånd; aerodynamik; motstånd; Fluid mechanics; Strömningsmekanik; Vehicle engineering; Farkostteknik

Record Details Similar Records

❌

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^{th} Edition):

Bergman, D. (2009). Modelling & implementation of Aerodynamic Zero-lift Drag into ADAPDT. (Thesis). Mälardalen University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7459

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^{th} Edition):

Bergman, David. “Modelling & implementation of Aerodynamic Zero-lift Drag into ADAPDT.” 2009. Thesis, Mälardalen University. Accessed April 20, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7459.

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^{th} Edition):

Bergman, David. “Modelling & implementation of Aerodynamic Zero-lift Drag into ADAPDT.” 2009. Web. 20 Apr 2021.

Vancouver:

Bergman D. Modelling & implementation of Aerodynamic Zero-lift Drag into ADAPDT. [Internet] [Thesis]. Mälardalen University; 2009. [cited 2021 Apr 20]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7459.

Note: this citation may be lacking information needed for this citation format:

Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bergman D. Modelling & implementation of Aerodynamic Zero-lift Drag into ADAPDT. [Thesis]. Mälardalen University; 2009. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7459

Not specified: Masters Thesis or Doctoral Dissertation