High-cycle fatigue test method for blisk

Abstract

The invention discloses a high-cycle fatigue test method for a blisk. The method comprises the following steps that: a clamp is designed and manufactured; modal calculation, modal testing and frequency response testing are performed on the clamp, and the first-order inherent frequency, damping ratio and vibration mode of the blisk are tested under free and holding states; a blade maximum stress area is calculated through a finite element method; a blade maximum stress point is determined through a strain gage bonding method; the relation curve of blade tip maximum displacement and stress is calibrated; blade frequency weight balancing design is carried out; test accompanying blades are monitored simultaneously by a monitoring system; and a fatigue test is started from a blade with the smallest frequency. Compared with a traditional blade cutting fatigue test method, the test method of the invention has the advantages that: the testing boundary condition of the blades of the blisk is closer to an actual using condition; the blisk is not damaged; test data errors caused by blade cutting surfaces are reduced; a test period is shortened; and test costs are reduced.

Description

technical field [0001] The invention relates to the technical field of mechanical vibration testing, in particular to a high-cycle fatigue testing method for an integral blisk. Background technique [0002] The overall blisk is a combination of blades and blisks through advanced technology. Compared with conventional blisks, the connecting tenons and tenon grooves are omitted, which greatly simplifies the structure, reduces the weight, and reduces the failure rate. The engine's thrust-to-weight ratio It has been improved, but the vibration and fatigue damage of the overall blisk are extremely prominent. The blade fatigue test of the overall blisk has so far been cutting the blade from the blisk, and then doing the fatigue life / limit of each blade. There are several problems in this test: one is that the blisk is completely destroyed after the test; The second is that the boundary conditions of the blade test are far from the boundary conditions of the use environment; the t...

AI Technical Summary

Problems solved by technology

The blade fatigue test of the overall blisk has so far been cutting the blade from the blisk, and then doing the fatigue life / limit of each blade. There are several problems in this test: one is that the blisk is completely destroyed after the test; The second is that the boundary conditions of the blade test are far from the boundary conditions of the use environment; the third is that the cutting process has a certain influence on the test data

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