大型船用柴油机活塞多腔振荡冷却的强化机制  

Enhanced Cooling Mechanism of Piston Multi-Cavity Oscillation Cooling in a Large Marine Diesel Engine

作　　者：王兆文[1] 周冬 梁刚[2] 周培 徐明焘 成晓北[1] Wang Zhaowen;Zhou Dong;Liang Gang;Zhou Pei;Xu Mingtao;Cheng Xiaobei(School of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Shanghai Marine Diesel Engine Research Institute,Shanghai 201108,China)

机构地区：[1]华中科技大学能源与动力工程学院,湖北武汉430074 [2]中国船舶重工集团公司第七一一研究所,上海201108

出　　处：《内燃机学报》2021年第4期367-376,共10页Transactions of Csice

基　　金：国家自然科学基金资助项目(51576083).

摘　　要：活塞是内燃机中热负荷和机械负荷最大的零部件之一,为了确保内燃机活塞的可靠性和寿命,大型船用柴油机往往采用振荡强化传热的方式进行活塞的冷却.为了理解振荡冷却的强化机制,首先进行了活塞冷却油腔壁面对流换热系数的分析,分解出常规流动换热分量、振荡强化换热分量和射流冲刷换热分量,并具体分析了振荡强化换热分量、射流冲刷换热分量和常规流动换热分量的分布特征.随后,基于正交设计方法,研究了活塞振荡腔不同结构参数对活塞内、外冷却油腔填充率和壁面对流换热系数的影响规律,为后续的活塞振荡冷却能力优化提供了方向.最后,针对原型活塞中内冷却油腔冷却能力不够的问题,进行了活塞振荡腔结构的优化.Piston is one of the engine components with the largest thermal load and mechanical load.The piston oscillation cooling method is often used in the large marine diesel engines to enhance the heat transfer across the piston in order to ensure the reliability and lifetime of the piston.In order to understand the heat transfer strengthening mechanism of piston oscillation cooling,the total wall convective heat transfer coefficient in the piston cooling oil chamber was firstly decomposed into three parts:the conventional flow heat transfer,oscillating heat transfer and the jet flushing heat transfer.Then,the distribution characteristics of the oscillating heat transfer,the jet flushing heat transfer and the conventional flow heat transfer were analyzed by using the orthogonal design method,which can provide an optimization direction for the piston cooling design.Finally,the structure of the piston oscillation chamber was optimized on a large marine diesel engine and the issue of the insufficient cooling capacity in the inner cooling oil chamber was solved.

关 键 词：大型船用柴油机 活塞 振荡冷却 壁面对流换热系数 双腔结构 正交设计 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]