This paper provides a numerical analysis model of unsteady heat trans-fer in piston-liner set of an internal combustion engine.The model simulates the un-steady heat transfer process among the combustion mixture,pisto...This paper provides a numerical analysis model of unsteady heat trans-fer in piston-liner set of an internal combustion engine.The model simulates the un-steady heat transfer process among the combustion mixture,piston set,lubricantfilm,liner and coolant in a whole engine cycle,and can predict the temperature fluc-tuation and distribution on piston crown,inner surface of liner,piston ring and thelubricant film.A computer program is developed to calculate the unsteady heat trans-fer process of piston-liner system in a water-cooled diesel engine.展开更多
This paper deals with the coupling problem between the dynamic behaviors and the tribological behaviors of the piston-liner systems in multi-cylinder internal combustion engines. Firstly, based on the correction of so...This paper deals with the coupling problem between the dynamic behaviors and the tribological behaviors of the piston-liner systems in multi-cylinder internal combustion engines. Firstly, based on the correction of some errors in the equation of piston secondary motion, which have been employed by many authors for several years, a detailed mathematical model for the coupling problem between the dynamical and tribological behaviors in the piston-liner systems of multi-cylinder internal combustion engines is presented. Secondly, the lubrication and friction between the liner and piston in each cylinder is included applying the average flow model of the Reynolds equation. Thirdly, the vibration of each liner is computed through the finite element model of a four-cylinder engine block, by which not only the liner motions caused by the block vibration but also the local vibration and the local static deformation of each liner can be figured out and taken into account. Through theoretical analysis and computation, some conclusions can be drawn as: 1) Both the liner vibration and piston motion are different for different cylinder in a multi-cylinder internal combustion engine, and hence different piston-liner systems will have different tribological behaviors. 2) Different liners have coincident dynamic response on the whole, especially for the lower frequency components. However, differences still exist among the vibrations of different liners, and these differences are mainly owing to the higher frequency components. 3) The impacts of liner vibrations on the tribological behaviors in piston-liner systems are primarily ascribed to its higher frequency components.展开更多
以内燃机典型摩擦副缸套-活塞系统为研究对象,设计和搭建内燃机缸套-活塞系统状态监测试验台。针对传统最大熵方法分析润滑油中磨粒监测数据存在的缺点,提出改进的分数矩最大熵方法(Fractional Moment Maximum Entropy Method, FM-MEM)...以内燃机典型摩擦副缸套-活塞系统为研究对象,设计和搭建内燃机缸套-活塞系统状态监测试验台。针对传统最大熵方法分析润滑油中磨粒监测数据存在的缺点,提出改进的分数矩最大熵方法(Fractional Moment Maximum Entropy Method, FM-MEM),并结合食肉植物优化算法(Carnivorous Plant Algorithm, CPA)对关键参数进行寻优求解。对润滑油中磨粒监测数据进行阈值划分,实现内燃机健康状态评估,然后将理论与试验相结合,以在线磨粒监测为主,从润滑油磨粒、理化指标以及表面形貌3个方面对内燃机缸套-活塞系统的运行状态进行监测,分析低速工况下缸套-活塞系统各个时间段的磨损健康状态及磨粒含量变化趋势,通过内燃机整机的在线磨粒监测试验,证明该方法可实现对内燃机缸套-活塞系统的实时状态监测。展开更多
文摘This paper provides a numerical analysis model of unsteady heat trans-fer in piston-liner set of an internal combustion engine.The model simulates the un-steady heat transfer process among the combustion mixture,piston set,lubricantfilm,liner and coolant in a whole engine cycle,and can predict the temperature fluc-tuation and distribution on piston crown,inner surface of liner,piston ring and thelubricant film.A computer program is developed to calculate the unsteady heat trans-fer process of piston-liner system in a water-cooled diesel engine.
基金the Major Program(Grant No.59990470) of National Natural Science Foundation of Chinathe General Program(Grant No.50175088) of National Natural Science Foundation of China.
文摘This paper deals with the coupling problem between the dynamic behaviors and the tribological behaviors of the piston-liner systems in multi-cylinder internal combustion engines. Firstly, based on the correction of some errors in the equation of piston secondary motion, which have been employed by many authors for several years, a detailed mathematical model for the coupling problem between the dynamical and tribological behaviors in the piston-liner systems of multi-cylinder internal combustion engines is presented. Secondly, the lubrication and friction between the liner and piston in each cylinder is included applying the average flow model of the Reynolds equation. Thirdly, the vibration of each liner is computed through the finite element model of a four-cylinder engine block, by which not only the liner motions caused by the block vibration but also the local vibration and the local static deformation of each liner can be figured out and taken into account. Through theoretical analysis and computation, some conclusions can be drawn as: 1) Both the liner vibration and piston motion are different for different cylinder in a multi-cylinder internal combustion engine, and hence different piston-liner systems will have different tribological behaviors. 2) Different liners have coincident dynamic response on the whole, especially for the lower frequency components. However, differences still exist among the vibrations of different liners, and these differences are mainly owing to the higher frequency components. 3) The impacts of liner vibrations on the tribological behaviors in piston-liner systems are primarily ascribed to its higher frequency components.
文摘以内燃机典型摩擦副缸套-活塞系统为研究对象,设计和搭建内燃机缸套-活塞系统状态监测试验台。针对传统最大熵方法分析润滑油中磨粒监测数据存在的缺点,提出改进的分数矩最大熵方法(Fractional Moment Maximum Entropy Method, FM-MEM),并结合食肉植物优化算法(Carnivorous Plant Algorithm, CPA)对关键参数进行寻优求解。对润滑油中磨粒监测数据进行阈值划分,实现内燃机健康状态评估,然后将理论与试验相结合,以在线磨粒监测为主,从润滑油磨粒、理化指标以及表面形貌3个方面对内燃机缸套-活塞系统的运行状态进行监测,分析低速工况下缸套-活塞系统各个时间段的磨损健康状态及磨粒含量变化趋势,通过内燃机整机的在线磨粒监测试验,证明该方法可实现对内燃机缸套-活塞系统的实时状态监测。
