An experimental and computational program has been conducted to obtain data on the effects of distributed surface roughness on blunt bodies. Sphere-cone and hemisphere geometry wind tunnel models with both pattern and sand-grain distributed surface roughness were tested at Mach 6 across a free stream Reynolds number range of Re,*, = 3.0×l0~6/ft to Re_∞ = 8.3×10~6/ft. Laminar, transitional and turbulent surface heating data were obtained using global phosphor thermography. Roughness-augmented, turbulent heating levels from 1.0 to 1.9 times the predicted smooth-wall turbulent levels were measured. Results matched general trends for roughness effects reported for other types of geometries and can be used for guidance in the design of thermal protection systems for NASA exploration missions.
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