基于变分模态分解的多缸柴油机缸套振动差异分析  

Difference analysis of cylinder liner vibrations in multi-cylinderdiesel engine based on variational modal decomposition

作　　者：李林涛 曹恒超 朱桂香 李国兴[1] 刘东 刘培毓 史威威 LI Lintao;CAO Hengchao;ZHU Guixiang;LI Guoxing;LIU Dong;LIU Peiyu;SHI Weiwei(Vechicle Engineering Department,Taiyuan University of Technology,Taiyuan 030024,China;Weichai Power Co.,Ltd.,Weifang 261061,China)

机构地区：[1]太原理工大学车辆工程系,太原030024 [2]潍柴动力股份有限公司,山东潍坊261061

出　　处：《振动与冲击》2024年第3期233-240,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金青年基金(51805353);山西省回国留学人员科研资助项目(HGKY2019041)。

摘　　要：多缸柴油机缸套振动噪声响应的差异导致缸套润滑、磨损及穴蚀现象不同,引起缸套可靠性差异并缩短整机使用寿命,研究差异的产生原因有助于柴油机的维护与设计优化。内燃机振动噪声的主要来源是燃烧冲击与活塞二阶运动引起的缸套敲击,而多缸柴油机缸套振动噪声的差异主要来源于活塞敲缸。以某重型六缸柴油机为研究对象,基于变分模态分解技术对多缸振动响应差异开展了溯源分析。建立了活塞敲缸动力学计算模型并通过试验验证了参数设置的合理性,通过变分模态分解从振动响应中提取了主要频率成分与相关模态。结果表明:多缸柴油机各缸振动幅值分布趋势一致,缸套中上部的振动最剧烈;各缸振动差异与机体模态特性有关,缸套间振动差异与机体第7阶模态振型趋势一致,体现为第6缸振动最强,第2缸振动最弱。Differences in vibration and noise responses of cylinder liners in multi-cylinder diesel engines cause different lubrication,wear and pitting phenomena to lead to differences in cylinder liner reliability and shortening the overall service life.Studying reasons of differences is conducive to maintaining and design optimization of diesel engines.Main sources of internal combustion engine vibration noise are combustion shock and cylinder liner knocking caused by second-order piston motion,while differences in cylinder liner vibration noise in multi-cylinder diesel engines mainly come from piston knocking.Here,taking a heavy-duty 6-cylinder diesel engine as the study object,traceability analysis was performed for differences in multi-cylinder vibration responses based on variational modal decomposition(VMD)technique.Dynamic calculation model for piston knocking was established and the rationality of parametric setting was verified through tests.Main frequency components and related modes were extracted from vibration responses with VMD.The results showed that distribution trend of vibration amplitude in each cylinder of a multi-cylinder diesel engine is consistent,vibrations in middle and upper parts of cylinder liners are the most severe;vibration differences in various cylinders are related to modal characteristics of engine body,vibration differences in cylinder liners and the 7th order modal shape of engine body have consistent trend;vibration of the 6th cylinder is the strongest,vibration of the 2nd cylinder is the weakest.

关 键 词：柴油机 缸套振动 动力学模型 变分模态分析 

分 类 号：TK423[动力工程及工程热物理—动力机械及工程]