内燃机工程2017，Vol.38Issue(2)：96-100,106,6.DOI:10.13949/j.cnki.nrjgc.2017.02.017
基于热机耦合的柴油机活塞热应力及疲劳寿命分析
Thermo-Mechanical Analysis of Piston Thermal Stress and Fatigue Life for Diesel Engine
摘要
Abstract
A finite element model of a piston including its skirt profile, optimized combustion chamber and oil gallery was established to investigate its temperature field, thermal stress and fatigue life at the rated condition by means of the finite element software PERMAS.Besides that, the sizes of the piston ring grooves and skirt profile were measured after a thermal shock test for 800h.The analysis results show that high temperature areas are mainly found at top of the piston, with the maximum temperature reaching about 301℃, and the mean temperature reaching 194℃ is found in the top ring insert, much lower than 230℃ for oil coking.So they are all acceptable even when the fuel injection quantity is increased by 20%.The piston inclines to the thrusting side under the coupled thermo-mechanical force, and the thrusting side bears a stress of 44N/mm2.The peak stress of about 98N/mm2 in piston pin bore is found at the rear end of the bore and they all are acceptable.The lowest piston fatigue life occurs at the bottom and bowl rim of the combustion chamber, and their theoretical service lives are 6.9 and 7.7 respectively, and the sizes of piston ring grooves and skirt profile have a little change after the 800h test, satisfying the requirements of use.关键词
柴油机/活塞/热负荷/疲劳寿命/有限元分析Key words
diesel engine/piston/thermal load/fatigue life/finite element analysis分类
能源科技引用本文复制引用
许广举,李铭迪,赵洋,陈庆樟,李学智..基于热机耦合的柴油机活塞热应力及疲劳寿命分析[J].内燃机工程,2017,38(2):96-100,106,6.基金项目
国家自然科学青年基金项目(51506011) （51506011）
江苏省自然科学青年基金项目(BK20160406) （BK20160406）
江苏省高校自然科学研究面上项目(15KJB470001) （15KJB470001）
苏州市应用基础研究项目(SYG201515) （SYG201515）
