转换活门密封对航空发动机数控系统通道切换的影响分析及改进

为改进液压机械装置(HMU)中主、备控制通道间的切换性能,避免航空发动机数控系统出现通道切换异常,采用试验及AMESim仿真结合的方法分析转换活门摩擦力对通道切换性能的影响,结果表明,摩擦力越大转换活门运动越慢,据此根据数控系统的设计需求反推转换活门处摩擦力的要求.采用ANSYS仿真获取转换活门动密封中聚四氟乙烯保护圈...

Analysis and Improvement of Sealing Structure of Transfer Valve on FADECs Channel Switching

In order to improve the performance of channel switching in a certain type of hydro mechanical unit (HMU) and avoid channel switching failed in the full authority digital engine control system (FADECs), the influence of friction on the channel switching performance are studied by mean of experiment and AMESIM simulation analysis, the results show that the larger the friction force, the slower the transfer valve movement. According to the design requirements of the FADECs, the friction requirements at the transfer valve are deduced. Then ANSYS is used to obtain the relationship between the size of polytetrafluoroethylene protection ring and friction force in the dynamic seal of transfer valve. Considering the requirements of friction force obtained before, combined with the actual design tolerance of the product, the design of protection ring at the transfer valve is improved. Finally, the experimental verification shows that the improved transfer valve seal can make the FADECs channel switch normally, at the same time, it does not affect the sealing effect of the transfer valve, and it provides an effective reference for the follow-up similar design.