基于ESLM热机耦合结构动态优化设计  

Dynamic Optimization Design of Thermo-Mechanical Coupling Structure Based on ESLM

作　　者：郭计云 贾权 郭巨寿 张艳岗[3] GUO Jiyun;JIA Quan;GUO Jushou;ZHANG Yangang(School of Mechanical and Electrical Engineering,Shanxi Datong University,Datong Shanxi 037003,China;The North General Power Group Co.,Ltd.,Datong Shanxi 037036,China;School of Energy and Power Engineering,North University of China,Taiyuan Shanxi 030051,China)

机构地区：[1]山西大同大学机电工程学院,山西大同037003 [2]北方通用动力集团有限公司,山西大同037036 [3]中北大学能源与动力工程学院,山西太原030051

出　　处：《机床与液压》2022年第19期83-88,共6页Machine Tool & Hydraulics

基　　金：山西省基础研究计划资助项目(20210302123069)。

摘　　要：等效静态负载法(ESLM)为动态响应优化技术提供了有效的解决方案,并用于具有单个机械负载的支架、横梁、杆和薄板等简单结构或网格要求较低的结构,但在热机械负荷的耦合作用下研究很少。因此,基于ESLM的热力机械耦合结构动态优化方法的研究具有一定的意义和价值。结合热弹性与等效静态方法,在热负荷与机械负荷耦合作用下,得出动态负荷的等效静态转换机制,并以悬臂束为例,验证热物理场和热结构中的等效理论,这同样适用于耦合物理。以典型的瞬态热力机械耦合结构——柴油发动机活塞为研究对象,通过活塞-热-机械耦合的瞬态动力学分析,提取16个关键位置的应力和位移结果,进行等效转换计算。结果表明:等效转换前后被检查区域的最大等效应力误差在3%以内,最大位移误差在2%以内。进一步分析比较活塞热力负荷作用下的静态优化和基于ESLM的动态优化结果,第一环槽的两个优化活塞变形、应力和温度相似,但ESLM动态优化与静态优化相比使活塞质量降低4.7%。研究成果证明了基于ESLM的动态优化方法的优势。The equivalent static load method(ESLM)provides an effective solution for dynamic response optimization technology,and is used in simple structures such as trusses,beams,rods,and thin plates that bear single mechanical load,or structures with lower grid requirements.But there are few researches under the coupled effect of heat-mechanical load.Therefore,the research of dynamic optimization method of heat-mechanical coupling structure based on ESLM has certain significance and value.Combining thermoelasticity with the equivalent static method,the equivalent static conversion mechanism of dynamic load under the coupling effect of thermal load and mechanical load was derived,and cantilever beam was taken as an example to verify the equivalent theory in thermophysical field and thermal-structure.The same applied to coupled physics.Taking a typical transient thermal-mechanical coupling structure:a diesel engine piston as the research object,the stress and displacement of the 16 key positions were extracted through the transient dynamics analysis of the piston-thermal-mechanical coupling,and the equivalent conversion calculation was carried out.The results show that the maximum equivalent stress error of the inspected area before and after equivalent transformation is within 3%,and the maximum displacement error is within 2%.Further analysis and comparison of the static optimization under the action of the piston thermomechanical load and the dynamic optimization based on ESLM show that the two optimized piston deformation,stress and temperature of the first ring groove are similar,but for the ESLM-based dynamic optimization,the piston mass is reduced by 4.7%compared to the static optimization.The research results fully prove the superiority of the ESLM-based dynamic optimization method.

关 键 词：活塞 动态优化 等效静态负载法 等效热负荷 

分 类 号：TK422[动力工程及工程热物理—动力机械及工程]