关键词: 汽车空调管路；随机振动；强度

Abstract: Aiming at the problem of cracking near the weld of air conditioning pipeline of a certain passenger car during the road test, random vibration finite element analysis is carried out on the basis of prestressed modal analysis, and it is found that the weak part of the pipeline is consistent with the road test fracture part. The weld size of the pipeline and joint is optimized by increasing the fillet size of the weld, and random vibration finite element analysis is carried out again. The results show that the maximum stress in the three vibration directions of the fracture weld is reduced by 9.8%, 29.5% and 45.2% respectively, and the maximum stress is reduced from 112.1 MPa to 86.1 MPa, which is lower than the yield limit of the material and meets the strength requirements. The study provides a reference for finite element analysis of random vibration of automotive air conditioning pipelines and strength optimization of welded structures.

Key words: Automobile air conditioning pipeline; Random vibration; Strength