Turbulent Aeroheating Testing of Mars Science Laboratory Entry Vehicle

摘要

An experimental investigation of turbulent aeroheating on the Mars Science Laboratory entry vehicle heat shield has been conducted in the Arnold Engineering Development Center Hypervelocity Wind Tunnel No. 9. Testing was performed on a 6 in. (0.1524 m) diameter Mars Science Laboratory model in perfect-gas N2 in the tunnel's Mach 8 and Mach 10 nozzles at freestream Reynolds numbers of 4.1 × 10~6-49 × 10~6 ft (1.3 × 10~7-16 × 10~7 m) and 1.2 × 10~6-19 × 10~6 ft (0.39 × 10~7-62 × 10~7 m), respectively. These conditions were sufficient to span the regime of boundary-layer flow from completely laminar to fully developed turbulent flow over the entire forebody. A supporting aeroheating test was also conducted in the Langley Research Center 20 Inch Mach 6 Air Tunnel at freestream Reynolds numbers of 1 x 10~6-7 × 10~6 ft (0.36 × 10~7-2.2 × 10~7 m) to help corroborate the Tunnel 9 results. A complementary computational fluid dynamics study was conducted in parallel to the wind-tunnel testing. Laminar and turbulent predictions were generated for the wind-tunnel test conditions and comparisons were performed with the data for the purpose of helping to define uncertainty margins on predictions for aeroheating environments during entry into the Martian atmosphere. Data from both wind-tunnel tests and comparisons with the predictions are presented herein. It was concluded from these comparisons that for perfect-gas conditions, the computational tools could predict fully laminar or fully turbulent heating conditions to within ± 12 % or better of the experimental data.