Optimum design of ablative thermal protection systems for atmospheric entry vehicles

Abstract

The Thermal Protection System (TPS) provides spacecrafts entering the atmosphere with the thermal insulation from the aerothermodynamic heating. The design of such a subsystem is very critical, considering that its damage can lead to a catastrophic failure of the whole entry system, in particular if ablative materials are considered. In order to design an ablative TPS, in fact, a reliable numerical procedure, able to compute surface recession rate, pyrolysis and internal temperature histories under severe heating conditions, is necessary. Indeed, the TPS needs to be sized to effectively shield the spacecraft from the high heat fluxes acting during the atmospheric entry phase. At the same time, its weight has to be the minimum value able to guarantee a suitable protection.This article aims to describe an optimization procedure for the design of ablative heat shields. In particular, in the present work, the numerical method is applied to the ablative TPS of the hypersonic reentry capsule Stardust.