【作者】 王新刚；

【导师】 贺建民；

【作者基本信息】 重庆理工大学 ， 车辆工程， 2009， 硕士

【摘要】 发动机曲轴连杆机构是高速旋转部件,其运动过程是发动机产生振动的一个主要原因,机构受到交变载荷的作用,某些部位的交变应力会达到很高的数值,容易产生疲劳破坏。如果在仿真过程中只考虑构件为刚体的情况,则不能精确地模拟机构的工作情况。本文运用三维绘图软件UG建立了JS183MQ发动机曲轴连杆机构的三维实体模型、运用有限元分析软件MSC.Patran/Nastran及机械系统动力学仿真软件MSC.Adams建立了曲轴连杆机构的刚柔耦合模型,进行了动力学仿真,得到了曲轴、连杆的动态应力。运用专业疲劳分析软件MSC.Fatigue对机构进行全寿命分析,指出了疲劳破坏部位,为曲轴连杆机构的设计提供了参考。活塞承受很大的热负荷和机械负荷,其热负荷和强度是影响发动机耐久性和可靠性的关键问题。本文建立了活塞与活塞销的四分之一耦合模型,采用有限元分析软件ANSYS模拟了活塞的温度场,并进行了热应力分析、机械应力分析和热机耦合分析,并提出了相应的改进措施。更多还原

【Abstract】 The crankshaft and connecting rod mechanism in a engine are high-speed rotating components, the movement of the institutions is one of the main reasons about vibration of the engine, Organizations are affected by the role of alternating load. The alternating stress of some parts will reach a very high value, easy to have the fatigue failure.If only considers each component as the rigid body in the simulation process,then can not accurately simulate the work of agencies. In this paper, the three-dimensional solid model of the institutions in JS183MQ engine has been established by using three-dimensional mapping software UG, and the coupled model of the rigid body and flexible body in the crankshaft connecting rod mechanism has been established by using finite element analysis software MSC.Patran/Nastran and mechanical system dynamics simulation software MSC.Adams, and the dynamic stress of the crankshaft and connecting rod through dynamics simulation has been achieved. The site of fatigue failure has been pointed out in the S-N analysis of institutions by using professional fatigue analysis software, and the results of this analysis can be referenced for the design of the crankshaft connecting rod mechanism.Pistons stands the great thermal load and mechanical load, thermal load and intensity of piston have greatly affected the durability and reliability of engine. A quarter of the coupling model about Piston and piston pin has been built in this paper, and the temperature field of piston has been simulated, and corresponding measures for improvement has been made after having analysised the thermal stress and mechanical stress and coupling stress.更多还原