Abstract:Aircraft actuator usually uses rubberPTFE combination Oring to seal the high pressure end surface of piston,while the sealing property of Oring will decline due to the friction heat produced by actuator.In order to study the heat effect on sealing property,the FEM model of combination Oring with consideration of the heatstructure coupling effect of triple nonlinear (material nonlinearity,geometric nonlinearity and boundary nonlinearity) was established by using ABAQUS software.The contact pressure distribution and sealing property of Oring under different oil pressures were analyzed.Based on the restart function of ABAQUS,the effect on friction heat by different oil pressures,sliding velocities and friction coefficients during the sliding process of piston was studied,the local temperature field distribution of O-ring was obtained,and the influence laws of three factors on the temperature field distribution were discussed.Analysis results indicate that the highest temperature of Oring during the process of sliding is increased with the increasing of oil pressure,sliding velocity and friction coefficient,among which friction coefficient has the most significant effect on the highest temperature of Oring.