Mechanical Property Analysis And Structure Optimization For The Unimproved And Improved Diaphragm Coupling

The diaphragm coupling has gained more popularity in aviation industry.As the key component of the power transmission between the aircraft accessories and engine accessories,it is of great importance for the safe and smooth operation of the aircraft and aero-engine.The research and development for the design technology of the diaphragm coupling has important theoretical and engineering value for Chinese aviation industry.In this paper,the static and dynamic characteristics analysis of a certain type diaphragm coupling was carried out.The main research contents and results were listed as follows:(1)Using finite element analysis software ANSYS,analyzed two types of diaphragm coupling in a free state and simplified the actual installation conditions of the natural frequencies and vibration mode.By comparative analysis,it was found that the natural frequencies of the improved diaphragm coupling rate were greater than unimproved of diaphragm coupling.It showed that the joint bearing can improve the rigidity of the disc coupling and the natural frequencies of the system.(2)The critical speed of the transmission shaft system before and after the improvement of the diaphragm coupling was calculated,and the critical speed characteristics of the transmission shaft and the influence of support stiffness on the critical speed were analyzed.The results showed that the improved diaphragm coupling increases the critical speed of the transmission shaft and thus improves the critical speed margin.In addition,the joint bearing made the sensitivity of the critical speed of the transmission shaft to the bearing stiffness improved.The dynamic characteristics of the improved diaphragm coupling are superior to those of the unimproved diaphragm coupling.(3)The static characteristics of the improved and unimproved diaphragm coupling under different loads were calculated and analyzed.The results showed that the static performance of the improved diaphragm coupling was better than unimproved diaphragm coupling,and it was more suitable for practical engineering applications.(4)Based on the incomplete fatigue test load spectrum of the unimproved diaphragm coupling,the axial load range of the unimproved diaphragm coupling was determined.Also,base on the load spectrum,the fatigue of the improved diaphragm coupling was analyzed.(5)Genetic algorithm and finite element method(FEM)were used to optimize the design of the joint bearing wear.The wear was decreased by 7.97% with both the statice and dynamic requirements fulfilled.