Aerodynamic Force Measurements of 10° Half-Angle Cone in JF12 Long-Test-Time Shock Tunnel

Aerodynamic force and moment measurements were conducted in JF12 long-test-time detonation-driven shock tunnel of Institute of Mechanics, Chinese Academy of Sciences. The test time of JF12 was 100~130 ms. The nominal Mach number was 7.0 and the exit diameter of the contoured nozzle was 2.5 m. The total enthalpy was 2.5 MJ/kg which duplicated the hypersonic flight conditions of 35 km altitude. The test model was standard aerodynamic model of 10° half-angle sharp cone. The length of the test model was 1500 mm with a mass of 50 kg. The aerodynamic forces were measured with a six-component strain balance. The angle of attack was set to be -5, 0, 5, 10 and 14°. The experimental results show that in the 100~130 ms test time, the signal of strain balance has 3~4 complete cycles. So the aerodynamic forces can be obtained directly by averaging the signal of balance without acceleration compensation. The uncertainty of force measurement in JF12 is less than 2%. The aerodynamic force coefficients of JF12 are in good agreement with that of conventional hypersonic wind tunnels with a difference of less than 2%. For this model under total enthalpy of 2.5 MJ/kg, the real-gas effects on aerodynamic force characteristics are not very evident.