Simulation of Radiation Experiments on Reentry Vehicles Using the New Radiation Database PARADE

Radiative heat flux can become significant during the entry of vehicles into planetary atmospheres. A new radiation database named PARADE has been developed in order to predict the radiation emitted from the flow around the vehicle. Furthermore, optical experiments can be analysed with this code. Due to the wide range of applications the code was kept general with respect to the state and the composition of the plasma. In particular, the species which can be considered are not limited by the code itself but depend only on the available data. New techniques were used especially for the discretisation of the wavelength array, since the quality of the results depends highly on an accurate discretisation of the atomic line shapes. For the simulation of flight experiments the radiation transport has to be computed as well. This was done using HERTA, a Monte-Carlo code, which takes reabsorption effects into account in a fully spectral manner. To demonstrate the capabilities of the new code system, radiative measurements made during the second BSUV flight experiments are simulated. Results show good agreement with predictions based on the NEQAIR code. However, measurements of molecular radiation could not be simulated satisfactory due to large uncertainties in the electronic excitation.