Study of Aerochemistry Around a 70 degree Half Angle Blunted Cone in CO2 Environment in the High Enthalpy Shock Tunnel

Four tests are performed in the HighEnthalpy Tunnel Goettingen (HEG) of the DLR at a free stream Mach number of approximately 10. Three CO2/N2 mixtures and one pare CO2 test gas case were used to study the entry into the Martian atmosphere. A blunted cone model with a cylindrical afterbody (sting)similar to a entry vehicle was investigated. To obtain information on the influence of defined parameters on the body back flow, especially of the reacting gas, the pressure distribution and the heat transfer rate along the body contour was measured with fast response surface thermocouples on the forebody and sensitive thin fil heat transfer gauges on the sting of the model. Flow visualisation of the region on the sting were the seperated fflow is turned by a second shock was imaged with the planar laser induced fluorescence system. Rough information about therotational temperature ratio across this shock was obtained for one run. For a pure CO2 test gas run a holographic interferogram and a laser schlieren picture was obtained.