Simulation of the Schiaparelli Entry and Comparison to Aerosciences Flight Data

Abstract

The European Space Agency flew an entry, descent, and landing demonstrator module called Schiaparelli that entered the atmosphere of Mars on 19 October 2016. The entry and descent instrumentation suite had sensors on both the heat shield and backshell and included forebody pressure transducers and thermocouples (Atmospheric Mars Entry and Landing Investigations and Analysis, or AMELIA), along with aftbody pressure transducers and heat flux (COMbined Aerothermal and Radiometer Sensors instrument package, or COMARS) and narrowband radiative heatflux sensors (Infrared CO Two Measurement, or ICOTOM). Because of the failed landing attempt, only a subset of the flight data was transmitted before and after plasma blackout. The goal of this paper is to present comparisons of the flight data with calculations using NASA’s aerodynamic and aeroheating simulation tools. Simulations were conducted at various angles of attack to compare against forebody pressure data and to infer the angle of attack used in full three-dimensional simulations to calculate the total heat flux at the sensor locations. Comparisons with the COMARS total heat flux data and backshell pressure data are presented. Furthermore, due to the sparse dataset, results are also compared with the reconstructed heat flux, which was calculated from an inverse analysis of the AMELIA thermocouple data. The simulations agree within 16% for both the total heat flux measured in flight and the heat flux reconstructed from the thermocouple data. A potential link between the Schiaparelli high spin rate observed during entry as documented in the anomaly report and the unexpected stagnation point pressure measurement is also discussed.