摘要
为了准确预测活塞疲劳寿命,提高活塞工作可靠性和使用耐久性,以某型号高强化柴油机为研究对象,结合活塞头部工作温度测试,建立了基于流固耦合传热的活塞疲劳寿命预测有限元仿真模型,计算分析了活塞的疲劳寿命;采用单因素扫值法研究了内冷油腔距活塞顶面距离、销座长度、燃烧室喉口圆角半径以及销孔直径4个主要结构参数对活塞疲劳强度的影响关系和变化规律.以内冷油腔距活塞顶面距离、销孔直径、燃烧室喉口圆角半径为优化变量,以活塞疲劳寿命为优化目标建立了响应面优化设计模型,优化了活塞主要结构参数.研究结果表明:减小内冷油腔距离活塞顶面距离,增加燃烧室喉口圆角半径和销孔直径,能有效改善活塞的热机负荷,提高疲劳寿命;通过优化响应面,在最优方案内冷油腔距活塞顶面距离35 mm、销孔直径54 mm、燃烧室喉口圆角半径2 mm下,活塞疲劳寿命提高18.9%.
This study aims to accurately predict piston fatigue life and improve piston working reliability and durability in use.The fatigue life of the piston was calculated and analyzed by establishing a finite element simulation model based on fluid-solid coupled heat transfer for piston fatigue life prediction,taking a model of highly reinforced diesel engine as the research object and combining with the piston head working temperature test;the fatigue life of the piston was calculated and analyzed by using the single-factor sweep method to study the influence of four main structural parameters,namely,the distance of the internal cooling oil chamber from the top surface of the piston,the length of the pin seat,the radius of the rounding of the combustion chamber throat and the diameter of the pin hole on the fatigue strength of the piston.The influence relationship and variation law of the four main structural parameters on the fatigue strength of the piston were studied.The response surface optimization design model was established with the distance of the internal oil chamber from the top surface of the piston,the diameter of the pin hole and the radius of the combustion chamber throat as the optimization variables and the fatigue life of the piston as the optimization target,and the main structural parameters of the piston were optimized.The research results show that reducing the distance of the internal oil chamber from the top surface of the piston,increasing the radius of the rounded corner of the combustion chamber throat and the diameter of the pin hole can effectively improve the thermal load of the piston and increase the fatigue life;through the response surface optimization,the fatigue life of the piston is improved by 18.9% under the optimal solution of the distance of the internal oil chamber from the top surface of the piston 35 mm,the diameter of the pin hole 54 mm and the radius of the rounded corner of the combustion chamber throat 2 mm.
作者
白高俊
雷基林
邓伟
周毅
袁晓麒
承宁
BAI Gaojun;LEI Jilin;DENG Wei;ZHOU Yi;YUAN Xiaoqi;CHENG Ning(Yunnan Province Key Laboratory of Internal Combustion Engines,Kunming University of Science and Technology,Kunming 650500,China;Wuxi Huaxing Electromechanical Manufacturing Co.,Ltd.,Wuxi,Jiangsu 214124,China)
出处
《昆明理工大学学报（自然科学版）》
北大核心
2022年第2期142-150,共9页
Journal of Kunming University of Science and Technology(Natural Science)
基金
国家自然科学基金项目(51665021)。
关键词
柴油机
铝活塞
流固耦合
疲劳寿命
优化设计
diesel engine
aluminum piston
fluid-coupling
thermal fatigue life
optimal design
