Design And Analysis Of Variable-Speed Helicopter Main Transmission Test Stand

Variable-speed rotor technology has great effect on the efficiency and overall performance of the helicopter,and its prospect is very broad.The variable speed of the rotor can be realized by changing the reduction ratio of the main transmission system of the helicopter.Variable-speed helicopter main transmission has become one of the key problems in variable-speed rotor technology.In order to carry out the research on main transmission system with variable-speed rotor,the design and analysis of the transmission test stand of the variable-speed helicopter are carried out in this paper.The main contents are as follows:Firstly,the main transmission systems of the helicopter with different structures were analyzed and compared.Dual-Clutch Transmission was chosen as a design object.The overall scheme and parameters of the testing stand were designed according to the design purpose and requirements.Power flow transmission of the main transmission system was analyzed as well.Transmission ratio of the gearbox was calculated to compared with the ratio of input speed and output speed.The correctness of the number of gear teeth could be proved in this way.The study above laid a foundation for the layout and parameter design of the test stand.Secondly,the key parts of the test stand were designed according to the structure parameters of the main transmission system.Parameter design of bevel gear in reversing gearbox along with ordinary gear train and planet gears in variable-speed gearbox was conducted.Stress analysis and strength check of the gears in variable-speed gearbox were conducted as well.The parameters design,material selection,heat load calculation and engagement process analysis of friction clutch friction disc were carried out too.Analysis of working principle and parameter design of overrunning clutch were conducted.Then,based on the wet friction clutch,a three-dimensional model of friction pairs was established and simulated.The flow field of lubricating oil between friction pairs and the temperature field characteristics of friction pair were analyzed.Furthermore,the influence of oil inlet speed on the temperature field of friction pair was analyzed as well.Finally,based on the design of variable-speed helicopter transmission test stand,threedimensional modeling,virtual assembly and interference analysis of parts and components were carried out by using SolidWorks.The kinematic equation of the variable-speed mechanism in the test stand was deduced in order to establish kinematics simulation model.Variation of the output speed of the transmission due to the clutch working state was obtained by SIMULINK.