Effects of Wear and Flank Clearance on Vibration Behavior of Gas Turbine Engine Gearbox

Abstract

The key defect of aircraft gas turbine engine gearboxes is the tooth flank wear and the corresponding increase in the flank clearance. The main danger of tooth wear is vibration generation resulting in fatigue failures of the engine structural elements. Using the example of tooth harmonics in the re-mating of teeth of the “sun gear – satellite” pair with frequency fZ1 and its sub harmonics with frequencies equal to one third and two thirds of it, as well as the vibration component that causes fatigue failures of engine structural elements, the change in the vibration state of the engine with the development of defects is shown. The sensitivity of the components under consideration to such defects is assessed. The potential danger of the component equal to two thirds of the tooth harmonics is revealed.