Research On Thermal-mechanical Coupled Analysis Of Launch Vehicle Cryogenic Tanks

Launch vehicle cryogenic tanks are the core of transport system of engines,from which engine energy come. On one hand,It can store liquid hydrogen and liquid oxygen. On the other hand,it also carry thermal protection system and provide installation base and space for instruments of other systems.Based on the function of a general FEM code ANSYS, a thermal-mechanical coupled analysis for a cryogenic tank during whole service process, including filling-up, storage, outflowing, storage again of the propellant liquid, has been carried out.The main contents of this paper are as follows:(1) The background and research trend at home and abroad is summarized.(2) Base on the feature of propellant tanks,FEM model is built. A numeric simulation process has canied out to get cryogenic tank's temperature and structure field with ANSYS.(3) Phase change of propellant is proposed,enthalpy-temprature curve is updated as Coulomb+stickness model,which make the simulation convergence easily.(4) In different work condition, stress and strain curves are contrasted. Some good results are acquired.The results obtained in this paper can provide designing,manufacturing and repairing lauch vehicle cryogenic tanks with reference,and corresponding computation method can supply theoretical basic for thermal—mechanical coupled analysis.