Numerical investigation of the impact of hypersonic shadowing on drag and heat transfer for a blunt body

A shock wave modification technique (hypersonic shadowing) is investigated and compared in effectiveness to selected previous methods of shock wave modification. The main goal of shockwave modification is to reduce drag due to pressure and/or heat transfer to a blunt body in hypersonic flow. Previous shockwave modification methods include forward facing physical spikes, mass injection, energetics, and electro-magnetic effects. Hypersonic shadowing uses small physical bodies embedded in the flow upstream of the blunt body to modify the shock wave. In this study hypersonic shadowing at Mach 6.5 and Mach 10 is numerically investigated using one or more embedded bodies. Flow fields are solved using the NASA 2D SPARK code. At Mach 6.5, one embedded body reduces the drag to 42.7% and the heat transfer to 78.5% of their baseline values. Two embedded bodies reduce drag and heat transfer to 20.9% and 55.9% of their baseline values, respectively. Three embedded bodies reduce the drag and heat transfer to 34.1% and 56.7% of baseline values. At Mach 10, one embedded body reduces drag and heat transfer to 27.7% and 70.4% of baseline values, respectively. Two embedded bodies reduce drag to 18.3% and heat transfer to 71.2% of their baseline values. Three embedded bodies reduce drag to 23.7% of its baseline value. Finally, control forces (lift and moment) are determined for a single embedded body located off the centerline in Mach 10 flow and compared to a flat plate at 2° angle of attack. The highest values of lift and moment occur at Z/D = 0.293. Lift augmentation is 32.4 and moment augmentation is 83.8 --Abstract, page iii