Date of Award
Master of Science
The interaction of shock waves and boundary layers in hypersonic flow has been studied for many decades under a variety of interests. Despite this continued interest, models still remain largely in development and require additional resources for justification of model assumptions. One simplifying approach seeks to model leading edge boundary layer flows based on the behavior of asymptotic limits in the flow physics. The asymptotic behavior of shock wave - boundary layer interactions is investigated for cases of strong interaction between the laminar boundary layer and attached leading edge shock wave on flat plates and compression ramps.
A commercially available computational fluid dynamics (CFD) solver is configured and automated to run on a high performance computing (HPC) system. A parametric study of the effects of hypersonic interaction parameter, body thermal condition, and ramp turning angle for large mach numbers (M > 4) and low Reynolds Number (Re < 3e+04) is conducted. The Navier-Stokes equations are solved iteratively for a laminar gas flow matching assumptions made by analytical models. Spacial modeling is limited to two dimensions and flow is assumed to be steady. The gas medium is modeled as compressible, calorically perfect air with unity Prandtl Number. Effects of thermal radiation are not accounted for in the current analysis. A limited grid dependence study shows good independence of solution from grid sizing and convergence of solution results.
Flat plate aerothermodynamics are examined for a range of isothermal and constant heat flux wall conditions. Shock wave and boundary layer behavior are examined along with properties at the wall. Isothermal compression ramps are also investigated to observe the effects of upstream influence in hypersonic flows dominated by viscous effects. Ramp wall pressure and shear stress show clear signs of upstream influence when compared to flat plates, eventually leading to flow separation at the ramp-plate junction.
Eli Ray Shellabarger
Shellabarger, Eli Ray, "Computational characterization of shock wave - boundary layer Interactions on flat plates and compression ramps in laminar, hypersonic flow" (2018). Graduate Theses and Dissertations. 16465.