Dynamic Modeling and Analysis of Helicopter Transmission System Considering the Effect of Input Conditions

The transmission system, which is integral to helicopters, is tasked with the responsibility of conveying the power torque to the rotor system. The transmission system has many rotating parts and abundant vibration sources. Constructing a dynamic model for a helicopter transmission system that encompasses multiple interfaces and interconnected subsystems, followed by conducting a dynamic analysis, holds substantial importance. At this paper, a dynamic model of the helicopter transmission system is formulated employing the method of concentrated masses. Transmission system vibration response was analyzed under constant torque operating conditions and variable torque operating conditions. Analysis results of the tail reducer, which is taken as an example, are presented. The results show that changes in both torque and speed have an impact on the vibration response over the input speed range of 0–3000 rpm.