摘要曲柄连杆机构是柴油机中最关键的部件之一，由于其在柴油机工作时承受复杂、交变的冲击载荷，因此它是设计柴油机时的重点和难点。传统设计和分析方法已经难以满足柴油机实际的需要，日益发展的多体动力学和有限元方法才能较准确地分析曲柄连杆机构并对其动力学运动进行仿真。86937

    为了更全面地研究柴油机曲柄连杆机构在工作过程中的运动规律和机构在运动过程中气缸气体力作用下曲轴的输出扭矩等问题，本文以4F20型柴油机为例，通过多体动力学仿真技术对柴油机曲柄连杆机构动力学性能进行了研究。本研究所用软件为多体动力学仿真软件ADAMS，应用ADAMS的3D建模功能分别构造了4F20柴油机曲柄连杆机构的各个部件的刚体模型，在此基础上，将各个部件装配在一起形成曲柄连杆机构的多刚体动力学模型。再通过ADAMS的仿真功能进行运动学分析和动力力学分析模拟，给出了动态仿真过程，得到了曲柄连杆机构各个构件的运动规律以及速度、加速度和位移随时间变化的情况，分析了各个构件在运行中的动态载荷。

    本文采用基于ADAMS的虚拟样机技术对曲柄连杆机构进行动力学仿真，具有很好的仿真效果，其简单方便人性化的操作、精确快速的仿真分析对于优化曲柄连杆机构设计，提高柴油机工作性能有很大的帮助。同时在内燃机设计中，采用该技术大大减小了样机的制造成本和试验成本，缩短了产品开发周期。

毕业论文关键词：柴油机、曲柄连杆机构、运动学、动力学、仿真模拟

Abstract    Crank connecting rod mechanism is one of the most important parts of diesel engine。 It is the key and difficult point of the design of diesel engine because of its complex and alternating impact load。 The traditional design and analysis methods have been difficult to meet the actual needs of the diesel engine, and the increasing development of multi-body dynamics and finite element method can be more accurate analysis of the crank link mechanism and its dynamic simulation。

    In order to do more comprehensive research of the diesel engine crank connecting rod mechanism in the working process of the movement rules and institutions in the movement process of output torque of crankshaft, cylinder gas force, this paper 4F20 type diesel engine as an example, on the dynamic performance of the diesel engine crank connecting rod mechanism were studied by means of multi body dynamics simulation technology。 this study used software for multibody dynamics simulation software ADAMS。 Adams is used in the 3D modeling function are constructed in various parts of the 4F20 diesel engine crank connecting rod mechanism of rigid body model, on the basis of this, all parts to be assembled together to form a multi rigid body dynamic model of crank and connecting rod mechanism。 Then through ADAMS simulation function of kinematic analysis and dynamic simulation analysis, provided the dynamic simulation process, it is concluded that the crank connecting rod mechanism of the various components of the movement and speed, acceleration and displacement along with the time change, analyzes the each component in the operation of the dynamic load。

      In this paper, based on ADAMS virtual prototype technology to crank and connecting rod mechanism for dynamic simulation, with very good simulation effect, the simple and convenient user-friendly operation, fast and accurate simulation analysis for the optimization design of crank and connecting rod mechanism, improve performance of diesel engine by the very big help。 At the same time in the design of internal combustion engine, the technology has greatly reduced the manufacturing cost of the prototype and test cost, shorten the product development cycle。