Analysis of thermo-mechanical fatigue life of regeneratively cooled thrust chamber based on phase field modeling
In order to analyze the stress and strain distribution of the regeneratively cooled thrust chamber in service and investigate the deformation and fatigue behavior under cyclic thermo-mechanical load,a thermal-elastic-plastic coupled fatigue fracture phase field model is established.The evolution of fracture order parameter is calculated and the fatigue life of the thrust chamber structure can be estimated.The distribution of temperature and the thermal eigenstrain is solved by the heat conduction equation.The stress-strain response and order parameter evolution are solved by using the stress equilibrium equation and phase field equation,respectively.The fatigue life of the thrust chamber structure could be evaluated by the cycle number when the order parameter reaches a critical value.The results indicate that the fail-ure occurs first at the middle point of the lower surface of the thrust chamber wall,with a fatigue life of a-bout 91 cycles.Under the cyclic temperature load,residual tensile strain is accumulated at that point.The inner wall's lower surface tends to collapse and be thinner until the structure fails.The phase field fa-tigue fracture model provides a novel methodology for predicting the fatigue life of the engine thrust cham-ber structure and helping the optimal design of the engine regeneratively cooled channel.
万方数据
维普
