Multi-Disciplinary Design Optimization under Uncertainty for Thermal Protection System Applications

Abstract

This paper presents an approach for performing Multi -disciplinary Design Optimization under Uncertainty (MDO -U) and an application for minimizing the thickness of the Thermal Protection System (TPS) for an entry vehicle configuration . Uncertainties due to material variability and the operating environm ent are considered. The value of considering uncertainty during the optimization process is demonstrated by comparing the performance of two optimal configurations, one identified through a deterministic approach and the other by considering uncertainty. Been able to account for uncertainty in engineering simulations and in product design is both important and challenging. In particular, during design optimization the performance of the optimized design typically lays closely to the boundaries of some of the constraints. Since variability alters the actual performance of a system, the optimal design can exhibit performance in the infeasible domain when the impact of the uncertainty has not been accounted properly during the optimization.