Multilevel Optimization Of Corrugated-Core Integrate Thermal Protection System

Thermal protection system(TPS)plays a vital role in the design of re-entry space vehicle.The existing thermal protection system has no load bearing ability.The thermal protection system covers the vehicle's structure,which leads to much additional weight.Therefore,idea of integrate thermal protection system(ITPS)is proposed.ITPS has both thermal protection as well as load bearing capabilities.By the application of ITPS,the structure of vehicle can be simplified and the weight efficiency.In recent years,much research has been done on ITPS,which focus on numerical simulation and experiment for cell structure.These works validate the feasibility of ITPS.But all these work are based on traditional analysis methods on conventional TPS.These traditional methods focus on the local thermal protection structure and omit the impact of global structure of vehicle.Corrugated-core sandwich panel ITPS is the main object in this thesis.A two-level optimization model is build.By this model,a synchronal optimization of inner structure of wing and outer ITPS is fulfilled.The two-level optimization consists of two stages.The first level is local optimization of ITPS and the second one is global optimization of vehicle's wing structure.The local optimization is based on the result of local thermal analysis and mechanical analysis.Equivalent stiffness of corrugated panel is introduced in local optimization model.By local optimization,the relation between equivalent stiffness and optimized areal-density of ITPS panel can be determined.Then,substituting the result of local optimization into global model,the final design of inner wing structure will be determined,as well as outer corrugated panel's parameters.