A Layout Method of Shock Absorber

Abstract

The present invention relates to a layout method for a shimmy damper and belongs to the field of helicopter kinetics physical design, comprising: performing dynamics modeling analysis on a layout scheme of the yaw damper; taking a hub center as the origin of a coordinate system and an extending direction of a blade K as X axis; establishing a coordinate system describing asymmetry in-blade layout of the blade K and a blade K+1 of the yaw damper; establishing a yaw damper-to-blade damping torque formula in the new scheme: a collected damping torque formula and a periodic damping torque formula; and according to a stiffness damping of yaw damper that needs to be satisfied, obtaining an optimal geometrical parameter. The present invention is applicable to blade yaw damper design of a machine under development or other helicopter models, is capable of meeting the requirements of eliminating both ground resonation and torsional vibration instability, and can improve the rotor yaw vibration damping and stiffness.

Description

technical field [0001] The invention belongs to the field of helicopter dynamic structure design, and in particular relates to a layout method of a novel helicopter damper and the design of parameters thereof. Background technique [0002] There are usually two layouts of the shimmy reducer, one is the independent layout, and the other is the symmetrical interleaf layout. [0003] For the independent layout, since the distance from the axis of the shimmy damper to the vertical hinge is limited by the space of the propeller hub, the damping and stiffness of the shimmy damper must be increased in order to achieve the required shimmy damping and stiffness. The dynamic load of the propeller hub, which is the deficiency of the independent layout of the shimmy reducer. However, the independent layout of the shimmy absorber can provide the same value of damping and stiffness for the rotor periodic and collective shimmy, and can meet the design requirements of eliminating ground re...

AI Technical Summary

Problems solved by technology

However, due to the symmetrical layout, the shimmy absorber does not provide damping and stiffness to the collective shimmy of the rotor, so it is necessary to add a band-stop filter to the engine control software system to prevent the occurrence of torsional vibration instability.

Although the use of a band stop filter can prevent the engine control system from diverging during the control process of the rotor speed, but because there is almost no shimmy damping, it is found in the actual model engineering that it is disturbed by manipulation and the speed fluctuates greatly, especially the structural load ratio of the transmission system. The independent layout is much larger, and the transmission gears often collide with each other, which poses a hidden danger to the structural life of the transmission system and the flight safety of the helicopter. It cannot be used for large-tonnage helicopters.

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