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Full-Text Articles in Aerospace Engineering
Study Of Magnetogasdynamic Flow Acceleration In A Scramjet Nozzle, Erik K. Ross
Study Of Magnetogasdynamic Flow Acceleration In A Scramjet Nozzle, Erik K. Ross
Theses and Dissertations
The research project studied the benefits of Magnetogasdynamic (MGD) acceleration on a scramjet nozzle. MGD is a technology that relies on electromagnetic fields to extract and/or add energy to flow fields. The scramjet engine in the "AJAX" concept proposed by D.I. Brichkii et al. (2001) of St. Petersburg, Russia would utilize an MGD power generator in the diffuser user which could potentially provide electrical power for the aircraft support systems and an MGD accelerator in the nozzle of the engine. Using an AFRL/VAAC CFD code that was modified for MGD computations, this project investigated the effect conductivity and load factor …
A Computational Study Of Thermo-Fluid Dynamics Of Pulse Detonation Engines, Alberto Davila Urresti
A Computational Study Of Thermo-Fluid Dynamics Of Pulse Detonation Engines, Alberto Davila Urresti
Master's Theses - Daytona Beach
The purpose of this thesis is to use a transient Computational Fluid Dynamics computer code written in FORTRAN 90 for full reaction kinetics, to perform an analysis of the physical processes and chemical phenomena occurring on a single cycle of an ideal Pulse Detonation Engine (PDE) using a stoichiometric mixture of H2 and O2. A small zone of high pressure and temperature is used to initiate the detonation wave in the PDE. A simple case with no chemical reactions and the same PDE geometry and “computational spark” is also tested. The speed of the wave relative to …
Validation Of Turbulence Models In The Beggar Code For Unsteady Flow, Kevin G. Storm
Validation Of Turbulence Models In The Beggar Code For Unsteady Flow, Kevin G. Storm
Theses and Dissertations
Validation of the turbulence models in the CFD code Beggar for unsteady turbulent flow are discussed. Six validation cases of the code are considered, three cases with the intent of validating the code without the turbulence model and three cases to validate the turbulence model itself. Finally, a more realistic simulation of a simplified store is examined. The turbulence models considered are the Baldwin-Lomax, Spalart-Allmaras, and a DES model. The conclusions made deal with necessary prerequisites to properly simulating unsteady turbulent flow and model selection. The prerequisites necessary in the Beggar code are a second order temporal discretization and the …
Boundary Layer Flow Control Using Plasma Induced Velocity, Brian E. Balcer
Boundary Layer Flow Control Using Plasma Induced Velocity, Brian E. Balcer
Theses and Dissertations
An examination of the effects of plasma induced velocity on boundary layer flow was conducted. A pair of thin copper film electrodes spanned the test section, oriented at thirty degrees from normal to the free stream flow. An adverse pressure gradient was imposed over the electrode configuration using a pressure coefficient profile similar to that associated with suction side of a Pac-B low pressure turbine blade. In addition, suction was applied to keep flow attached on the upper wall, inducing separation over the electrode. The electrode is supplied by an AC source at three different power levels with the free …
Development Of A Higher-Order Upwind Algorithm For Compressible Fluid Flow, Barry A. Croker
Development Of A Higher-Order Upwind Algorithm For Compressible Fluid Flow, Barry A. Croker
Theses and Dissertations
A global fourth-order solution method that incorporates compact differencing with Roe's approximate Riemann solver was investigated. This method was incorporated into a one-dimensional numerical simulation of the compressible Euler equations, and applied to a one-dimensional shock tube problem. The method was also extended to two dimensions, and applied to a two-dimensional shock tube problem and an advecting vortical structure problem on both rectilinear and curvilinear meshes. The results were compared to a third-order Roe scheme and a fourth-order compact difference scheme. An order of accuracy determination showed that it has an order of accuracy somewhere near fourth order, with absolute …
Numerical Analysis And Optimization Of The Ultra Compact Combustors, Roger T. Greenwood
Numerical Analysis And Optimization Of The Ultra Compact Combustors, Roger T. Greenwood
Theses and Dissertations
In an effort to increase thrust per weight ratio and decrease pollutant emissions of aero-turbine jet engines, a circumferentially burning Ultra Compact Combustor (UCC) with a Cavity-in-a-Cavity design has been developed. A numerical analysis of this design has been conducted and compared with experimental results. The CFD model has been validated through a wide range of conditions and four alternative physical configurations of the UCC have been modeled. Emissions, combustor efficiencies, temperature and velocity profiles, and pressure drop values were used as comparison parameters. Numerical results indicate that increasing the outflow area will increase the pressure drop over the combustor …