北京交通大学学报2023，Vol.47Issue(5)：91-97,7.DOI:10.11860/j.issn.1673-0291.20220148
动车组设备舱冷却单元铝合金立柱开裂成因研究
Study on causes of cracking in aluminum alloy columns of cooling unit in EMU equipment cabin
摘要
Abstract
To investigate the causes of cracking in the aluminum alloy columns of the EMU cool-ing unit,on-track tests are carried out on the unit frame and columns.This study obtains time and frequency domain characteristics of aerodynamic loads and vibration acceleration on the bot-tom plate and dynamic stress at key locations of the columns.Combining this with modal analy-sis,the reasons for column cracking are identified.Furthermore,the equivalent stress amplitude and fatigue damage value at 15 million km at the column's crack location are calculated.The re-sults show that when the train is running at high speed,the main frequencies of the aerodynamic load and vibration acceleration of the bottom plate are close to the main frequencies of dynamic stress near the column crack and the natural frequencies of the bottom plate deformation of the cooling unit frame.This suggests that the resonance of the bottom plate under aerodynamic load causes stress concentration at the welding seam of the lifting lug on the aluminum alloy support column,leading to cracks initiating from the concave weld toe of the fatigue-prone region.The damage value near the column crack at 15 million km exceeds 1,indicating a fatigue failure risk within the design lifecycle.关键词
动车组/时频分析/线路测试/冷却单元/气动载荷/振动加速度/疲劳损伤Key words
EMU/time-frequency analysis/on-track tests/cooling unit/aerodynamic load/vibration acceleration/fatigue damage分类
交通工程引用本文复制引用
王文静,董子钰,李博,杨广雪,张延蕾..动车组设备舱冷却单元铝合金立柱开裂成因研究[J].北京交通大学学报,2023,47(5):91-97,7.基金项目
中央高校基本科研业务费专项资金(2020JBM032) （2020JBM032）
国家自然科学基金(52075032) （52075032）
中国铁路总公司科技研究开发计划课题(K2022J003) Fundamental Research Funds for the Central Universities(2020JBM032) （K2022J003）
National Natural Science Foundation of China(52075032) （52075032）
Science and Technology Research and Development Program of China State Railway Group Co.,Ltd.(K2022J003) （K2022J003）
