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You searched for +publisher:"University of Tennessee – Knoxville" +contributor:("Kivanc Ekici, Rao V. Arimilli"). Showing records 1 – 3 of 3 total matches.

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University of Tennessee – Knoxville

1. Hight, Brad Harrison. Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes.

Degree: MS, Mechanical Engineering, 2014, University of Tennessee – Knoxville

Lithium (Li) behavior inside a high temperature Nb-Li leading edge heat pipe was successfully imaged under induction heating operation via neutron imaging. Startup and cool-down operations gave visual confirmation of bulk Li movement using both gravity assisted and inverted operating orientations. The pipe was imaged during an operation cycle from ambient conditions, heated to a steady state temperature of 908.8 0C, and allowed to cool below 200°C. The experiment was performed at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, and at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. Tomographic images of the heat pipe sample at ambient conditions were taken at NIST using three 5s exposures combined for each step, with a step angle of 0.18° resulting in 1001 projections. The reconstructed images gave insight into workmanship and Li wetting characteristics of the heat pipe. The cross sectional images allowed for visualization of the sample’s inside mesh wicking structure and Li distribution, giving understanding into structural workmanship that is critical for the pipe’s working efficiency. The reconstructions were used to create a 3-D rendering of the heat pipe and the inner lying Li distribution. Comparative heat transfer experiments were conducted for a heat pipe containing non-condensable gases (NCGs) and another sample that was free of NCGs, using a threaded stainless steel water jacket. The heat pipe containing no NCGs resulted in double the cooling heat flux for the same induction heating input power, with a maximum of 440 W being removed from its condenser at an input of 1800 W. The result of the experiment was used in conjunction with visual observation of the pipes under heating loads to confirm the negative impact of NCGs on a heat pipe. Future recommendations are to more realistically simulate hypersonic leading edge heating loads using localized heating instead induction heating. A butane-powered portable torch can be considered to localize heating to the leading edge and allow for higher test temperatures. The setup would be done in open air, allowing for combustion but would require a silicide anti-oxidation coating for the tested heat pipe surfaces. Advisors/Committee Members: Kenneth D. Kihm, Kivanc Ekici, Rao V. Arimilli.

Subjects/Keywords: Heat Pipes; Liquid Metal; Neutron Imaging; High Temperature; Niobium; Lithium; Aerodynamics and Fluid Mechanics; Heat Transfer, Combustion

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

APA (6th Edition):

Hight, B. H. (2014). Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/2773

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):

Hight, Brad Harrison. “Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes.” 2014. Thesis, University of Tennessee – Knoxville. Accessed February 20, 2019. https://trace.tennessee.edu/utk_gradthes/2773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Hight, Brad Harrison. “Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes.” 2014. Web. 20 Feb 2019.

Vancouver:

Hight BH. Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes. [Internet] [Thesis]. University of Tennessee – Knoxville; 2014. [cited 2019 Feb 20]. Available from: https://trace.tennessee.edu/utk_gradthes/2773.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hight BH. Neutron Imaging of Lithium (Li) Coolants inside High Temperature Niobium (Nb) Heat Pipes. [Thesis]. University of Tennessee – Knoxville; 2014. Available from: https://trace.tennessee.edu/utk_gradthes/2773

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Tennessee – Knoxville

2. Pemberton, Seth Allen. A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media.

Degree: MS, Mechanical Engineering, 2013, University of Tennessee – Knoxville

This thesis aims to investigate conjugate heat and mass transfer in porous media with an emphasis on textiles. Both hygroscopic materials, those that absorb water vapor, and non-hygroscopic materials are examined. A model was developed that utilizes COMSOL’s equation-based partial differential equation (PDE) interface which allows the user to input any equation(s) to be solved. By the use of experimental and numerical data each part of the model, i.e. flow field, gas diffusion, convection and vapor absorption, is verified. The accuracy of the equation-based unsteady flow field is verified by modeling the flow over a circular cylinder and extracting the lift and pressure coefficients. Gaseous diffusion in a porous medium (PM) is shown to agree with volume averaging theory. Steady state convection and diffusion is modeled and reveals the importance of mass diffusion in PM as well as how changes in material permeability, due to water vapor absorption, affect heat and mass transfer. Water vapor absorption yields a dynamic response under transient conditions, which results in significant temperature changes depending on textile fiber properties. Advisors/Committee Members: Kivanc Ekici, Rao V. Arimilli, Jay I. Frankel.

Subjects/Keywords: heat and mass transfer; porous media; Heat Transfer, Combustion

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

APA (6th Edition):

Pemberton, S. A. (2013). A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/2634

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):

Pemberton, Seth Allen. “A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media.” 2013. Thesis, University of Tennessee – Knoxville. Accessed February 20, 2019. https://trace.tennessee.edu/utk_gradthes/2634.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Pemberton, Seth Allen. “A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media.” 2013. Web. 20 Feb 2019.

Vancouver:

Pemberton SA. A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media. [Internet] [Thesis]. University of Tennessee – Knoxville; 2013. [cited 2019 Feb 20]. Available from: https://trace.tennessee.edu/utk_gradthes/2634.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pemberton SA. A Novel Approach to Multiphysics Modeling of Heat and Mass Transfer in Porous Media. [Thesis]. University of Tennessee – Knoxville; 2013. Available from: https://trace.tennessee.edu/utk_gradthes/2634

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Tennessee – Knoxville

3. Clark, Emily Buckman. Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method.

Degree: MS, Aerospace Engineering, 2013, University of Tennessee – Knoxville

Two-dimensional laminar flow over a circular cylinder was investigated in this work. Three cases were considered in which the cylinder was either stationary, in constant rotation, or in periodic rotation. The purpose of this work was to investigate the effects of a rotating cylinder for lift enhancement, drag reduction, and the suppression of vortex shedding. The governing coupled nonlinear Navier-Stokes equations were solved using a finite difference discretization and Newton’s method. In this way, three flow solvers were developed for this research: a steady solver, an unsteady time-accurate solver, and an unsteady harmonic balance solver. The force coefficients were of prime interest in this study. Favorable results were obtained using rotation as an active control for the flow over the cylinder. The cylinder in constant rotation resulted in lift enhancement, drag reduction and vortex suppression for increasing rotational speeds. Lift enhancement and drag reduction were also noted for a rotationally oscillating cylinder. The trade-offs for these goals were discussed. Lastly, a finite difference sensitivity analysis was performed for a rotationally oscillating cylinder with the harmonic balance solver. The mean drag coefficient was taken as the objective function, and the Strouhal number was the investigated design variable. The goal was to use the sensitivity analysis to determine a forcing frequency, which minimized the mean drag coefficient. Two iterative techniques were investigated, but neither converged to a minimum drag coefficient with the harmonic balance solver. It was determined that a minimum drag coefficient occurs near the boundary between the lock-on and non lock-on regions or in the non lock-on region, where the harmonic balance solver does not converge. Advisors/Committee Members: Kivanc Ekici, Rao V. Arimilli, Vasilios Alexiades.

Subjects/Keywords: vortex suppression; lift; drag; finite difference; active control; sensitivity; Aerodynamics and Fluid Mechanics; Aerospace Engineering; Engineering

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

APA (6th Edition):

Clark, E. B. (2013). Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/2402

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):

Clark, Emily Buckman. “Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method.” 2013. Thesis, University of Tennessee – Knoxville. Accessed February 20, 2019. https://trace.tennessee.edu/utk_gradthes/2402.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Clark, Emily Buckman. “Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method.” 2013. Web. 20 Feb 2019.

Vancouver:

Clark EB. Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method. [Internet] [Thesis]. University of Tennessee – Knoxville; 2013. [cited 2019 Feb 20]. Available from: https://trace.tennessee.edu/utk_gradthes/2402.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Clark EB. Analysis and Optimization of Unsteady Flow Past a Circular Cylinder Using a Harmonic Balance Method. [Thesis]. University of Tennessee – Knoxville; 2013. Available from: https://trace.tennessee.edu/utk_gradthes/2402

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.