Roughness induced laminar turbulent transition for hypersonic vehicles

For the design of sustainable hypersonic flight at Mach numbers above 5 or re entry vehicles like space capsules or the Space Shuttle, heat management is one of the crucial aspects of engineering. Besides the application of insulating materials and their development to be used in the heat shield, the generation of the heat through fluid dynamics processes in the boundary layer along the vehicle has to be known. As experiments for these flight conditions are either extremely expensive or subject to large errors, numerical simulations can bridge the gap between the lab environment and the full scale application.Laminar turbulent transition at hypersonic speeds is one of the key feature to understand the physics of the flow at high speeds and high temperatures as the heat load on the vehicle can change more than 10 fold if the flow becomes turbulent compared to a laminar flow. In this project, we investigate through high precision and high fidelity numerical simulations including chemical reactions (dissociation) and non equilibrium the influence of surface imperfections on the laminar turbulent transition. The surface roughness either comes from holes for screws, gaps between heat shield tiles or from the ablating material subject to burning at these extreme temperatures.     «

For the design of sustainable hypersonic flight at Mach numbers above 5 or re entry vehicles like space capsules or the Space Shuttle, heat management is one of the crucial aspects of engineering. Besides the application of insulating materials and their development to be used in the heat shield, the generation of the heat through fluid dynamics processes in the boundary layer along the vehicle has to be known. As experiments for these flight conditions are either extremely expensive or...     »