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Full-Text Articles in Aerospace Engineering
Effects Of Cone Tip Changes On Wall-Cooled Hypersonic Boundary Layer Transition And Turbulence, Mathew M. Major
Effects Of Cone Tip Changes On Wall-Cooled Hypersonic Boundary Layer Transition And Turbulence, Mathew M. Major
Theses and Dissertations
Boundary layer measurements took place at Air Force Research Lab’s (AFRL) Mach-6 Ludwieg tube hypersonic wind tunnel on a 7-degree half angle spherically blunted nose cone with a 1.5 mm radius to study the effects of a cooled surface on the transition process. Experiments compared uncooled and cooled flow conditions on the blunt-nosed model, and then compared to past data for a sharp-tipped cone of similar geometry. Cooling the surface delayed the onset of transition on the blunt nose model. Combining the effects of nose blunting and cooling further increased transition delay than each acting individually compared to the sharp-tipped …
Double Cone Flow Field Reconstruction Between Mach 4 And 12 Using Machine Learning Techniques, Trevor A. Toros
Double Cone Flow Field Reconstruction Between Mach 4 And 12 Using Machine Learning Techniques, Trevor A. Toros
Theses and Dissertations
No abstract provided.
Exploratory Measurement Of Recession Rates Of Low Temperature Ablators Subjected To Mach 6 Flow, Ross H. Kellet
Exploratory Measurement Of Recession Rates Of Low Temperature Ablators Subjected To Mach 6 Flow, Ross H. Kellet
Theses and Dissertations
The high speed/high-temperature effect of heat shield ablation was simulated in the low-enthalpy AFRL Mach 6 Ludwieg Tube using solid dry ice as a low-temperature sublimator. The experiments utilized both 21 half-angle cones and bi-conic models with a 7 ° half-angle leading edge followed by a 26° half-angle base contained within a cryogenic-cooled stainless steel holder. A method of fabricating dry ice test articles was developed using commercially procured dry ice and custom-made aluminum molds. Tests were performed at Mach 6.1 with a stagnation temperature of 490 K and stagnation pressures ranging from 40 - 500 psi. Unit Reynolds number …
Surrogate Modeling Of Computational Aerodynamic Responses For A Generic Hypersonic Vehicle, Jacob R. Johanik
Surrogate Modeling Of Computational Aerodynamic Responses For A Generic Hypersonic Vehicle, Jacob R. Johanik
Theses and Dissertations
In the field of multidisciplinary hypersonic vehicle design, striking the balance between the accuracy and efficiency of a predictive aerodynamic response model is a significant challenge. In response to this challenge, the objective of this thesis is to evaluate the aerodynamic performance of a Generic Hypersonic Vehicle (GHV) using the technique of surrogate modeling Computational Fluid Dynamic data points across a large range of flight conditions. To accomplish this, the full CFD process was conducted by preparing the vehicle geometry, generating a grid, computing the flow, and post-processing the data. A three-dimensional, quasi-random distribution of 1000 points defined the design …