在无油润滑工况下，密封面磨损是导致密封件性能降低及寿命丧失的关键因素. 结合有限元技术，基于修正的Archard磨损模型，建立盖封（CL）密封过程中密封件和活塞杆间的磨损-热-应力耦合数值模拟方法，分析磨损过程中密封件性能与寿命的变化规律及介质压力对密封特性的影响；基于所建立的仿真模型，采用正交试验设计法，以密封件密封面上最大接触压力降幅最小及密封件寿命最长作为优化目标，对CL密封中C形密封圈关键结构参数进行优化设计，得到最优组合方案；利用斯特林发动机活塞杆密封性能试验平台对数值模拟方法进行验证，并对磨损后CL密封接触面磨损状况进行测量，检测结果与仿真模拟结果较为一致，优化后密封件密封性能及使用寿命得到了提高.%The wear of the sealing surface is the key factor resulting in the declination of sealing performance and the loss of seal-life under the condition of oil free lubrication. A numerical simulation method of wear-thermal-stress coupling between seal and piston rod in the process of cap-seal (CL) sealing was established based on the finite element technique and the modified Archard wear model, and the change rule of seal performance and life in the process of wear and the effect of medium pressure on sealing characteristics were analyzed. The key structure parameters of C-ring in CL seal were optimized by applying the orthogonal design method based on the established simulation model, in order to realize the optimization target of getting minimum drop of maximum contact pressure in seal face and maximum seal-life, and the best parameter combination scheme was obtained. The results of numerical simulation and optimization design were verified by the experimental platform of Stirling engine piston rod seal performance test device, and the wear condition of contact surface of CL seal after wear was measured. The result of wear test was consistent with that of numerical simulation, and the sealing performance and life of the CL seal have been greatly improved after optimization, which confirms the accuracy of the numerical simulation method.
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