Numerical Studies on Reducing Aerodynamic Heating of a Re-entry Vehicle

It is important to understand the aerothermodynamics besides aerodynamics to design a high speed vehicle. A body travelling at high speed could generate enough heat to cause it to burst apart. Thus, a blunt nose design is used for a simple re-entry vehicle in order to achieve a detached shockwave (bow shock) and so dissipate more heat into the surrounding atmosphere. For blunt bodies versus sharp-edged, the ballistic coefficient is lower. The vehicle slows down higher in the atmosphere as a result, which lessens the aero-thermal loads it encounters. A basic design of existing Orion-based crew exploration vehicle travelling in a low hypersonic speed (Mach 6) is considered owing to the feasibility of available computational support. Computational fluid dynamics (CFD) study consisting of both qualitative and quantitative analyses has been done to further reduce the aerodynamic heating of the capsule. Ansys Fluent was utilized to capture the heat flux over the surface, velocity profiles, pressure, and temperature distribution surrounding the capsule. To reduce the aerodynamic heating while preserving other parameters (such as lift and drag) and a suitable ballistic coefficient, a variety of design enhancements can be made. Concave heat shield, a revolutionary design advancement that reduces aerodynamic heating, was therefore investigated in this work. A significant decrease in the aerodynamic heating is observed for the proposed design provided with a slight increment in drag which in turn is favourable.