Research On Disk Burst Speed Prediction Method Based On Failure Mode

Aeroengine disk is the main force-bearing structure and the most important parts of the aeroengines.During the acceleration of the engine,the disk may overturn and even cause the disk burst.Once the disk burst,it must be non-inclusive which will cause very serious consequences.Therefore,when designing the structure of the engine disk,it is necessary to ensure that the disk has sufficient strength reserves.Therefore,it is of great significance to accurately predict the disk burst speed and mode of the disk.This article mainly uses the traditional average stress method,Hallinan method,ultimate stress-strain method,and residual deformation method to predict the disk burst speed and mode,evaluates the applicability and reliability of the above prediction methods,and establishes a set of A process method for predicting the disk burst speed and mode.The main contents and conclusions are listed as follow:(1)To obtain accurate material mechanical properties,study the material notch strength ratio.First,the tensile test of GH4169 material was carried out,and the performance parameters and true stress-strain curves of the material at different temperatures were obtained.Then,through the notched tensile test,it was found that the tensile strength of the notched specimen of GH4169 material increased with the increase of the stress concentration factor,and the strength of the notched specimen was higher than that of the smooth specimen.(2)Design and test to verify the burst speed and failure mode of two types disks,and analyze the applicability and reliability of each burst speed calculation method.Among them,for the disk with a uniform thickness change throughout the meridian section,and there is no discontinuous structure such as eccentric holes,tongues and grooves,the failure mode is due to the continuous expansion of the central hole,and the entire meridian section reaches the ultimate strength of the material,causing the disk to break,based on In this failure mode,it is more effective to predict the burst speed of the disk by the average stress method.For the disk with a large variation in the thickness of the entire meridian section and an eccentric hole structure at the spoke,the failure mode is due to the stress concentration at the eccentric hole causing the disk to break.Based on this failure mode,the ultimate stress and strain method used to predict the disk burst speed is more accurate.(3)Complete the prediction and test verification of the burst speed and failure mode of a GH4169 material high-pressure compressor disk.The overall structure of the disk is composed of a spoke plate and a drum.There is an eccentric hole on the disk.According to the overall stress state of the disk calculated by finite element calculation,the failure mode of the disk is that the stress concentration at the eccentric hole causes cracking.Therefore,the ultimate strain method can accurately predict the burst speed of the disk,and the test results show the accuracy of the prediction method used in this paper.