4G63发动机曲轴设计及有限元分析

黑龙江工程学院本科生毕业设计

摘要

本设计以4G63发动机的相关参数作为参考，对四缸汽油机的曲柄连杆机构的主要零部件曲轴等进行了结构设计计算，并对曲柄连杆机构进行了有关运动学和动力学的理论分析与计算机有限元分析。

首先，以运动学和动力学的理论知识为依据，对曲柄连杆机构的运动规律以及在运动中的受力等问题进行详尽的分析，并得到了精确的分析结果。其次分别对曲轴进行详细的结构设计，并进行了结构强度和刚度的校核。再次，应用三维CAD软件：Pro/Engineer建立了曲柄连杆机构中曲轴的几何模型。而曲轴，作为发动机的主要运动部件，其性能优劣直接影响到发动机的可靠性和寿命。在周期性变化的动载荷作用下，曲轴内将产生交变的弯曲应力和扭转应力，极易在过渡圆角等应力集中部位发生弯曲疲劳破坏和扭转破坏。随着发动机的不断强化，曲轴的工作条件愈加苛刻。本文对发动机曲轴进行符合实际条件的建模，采用ANSYS对其进行三维有限元分析，研究了整体曲轴的变形和应力状况，根据应力响应结果并结合材料特性，校核了载荷下的强度，为发动机曲轴改进设计中的分析提供了理论依据。

关键词：发动机；曲柄连杆机构；受力分析；曲轴；Pro/E；有限元分析

I

黑龙江工程学院本科生毕业设计

ABSTRACT

The 4G63 engine design parameters as a reference, on four-cylinder gasoline engine crank crankshaft, etc. The main components of structural design calculations, and the crank was on the theory of kinematics and dynamics analysis Finite element analysis computer.

First, the kinematics and dynamics of theoretical knowledge as the basis, the motion law of crank rod system and the structural problems in sports, and a comprehensive analysis of the precise analysis results obtained. Next to the crankshaft respectively detailed structure design, and a structure strength and stiffness checking. Again, use 3d CAD software: Pro/e established in crank rod system of crankshaft geometric model. And, as the main engine crankshaft, its performance movement part quality directly affect the engine reliability and life expectancy. In periodically dynamic load, crankshaft will produce alternating within the bending stress of the torsional stress, easily with the stress concentration areas such as transitional fillet bending fatigue damage occurred and twisting damage. With the engine crankshaft constantly strengthened, the more harsh working conditions. This paper to accord with the actual conditions of engine crankshaft modeling, using ANSYS, the three-dimensional finite element analysis of the whole of the crankshaft research, according to the deformation and stress conditions stress response results and material properties, checked with the strength of the load for design improvement, the analysis engine crankshaft provides theoretical basis.

Key words: Engine；Crank；Stress Analysis；Crankshaft Pro / E；Finite Element Analysis

II

黑龙江工程学院本科生毕业设计

目录

摘要.........................................................................................................................................I Abstract ................................................................................................................................ II 第1章绪论 .. (1)

1.1 选题的目的和意义 (1)

1.2 国内外的研究现状 (2)

1.3 设计研究的主要内容 (3)

第2章曲柄连杆机构受力分析 (5)

2.1 曲柄连杆机构的类型及方案选择 (5)

2.2 曲柄连杆机构运动学 (5)

2.1.1 活塞位移 (6)

2.1.2 活塞的速度 (7)

2.1.3 活塞的加速度 (7)

2.2 曲柄连杆机构中的作用力 (8)

2.2.1 气缸内工质的作用力 (8)

2.2.2 机构的惯性力 (8)

2.3 本章小结 (16)

第3章曲轴的设计 (17)

3.1 曲轴的结构型式和材料的选择 (17)

3.1.1 曲轴的工作条件和设计要求 (17)

3.1.2 曲轴的结构型式 (17)

3.1.3 曲轴的材料 (18)

3.2 曲轴的主要尺寸的确定和结构细节设计 (18)

3.2.1 曲柄销的直径和长度 (18)

3.2.2 主轴颈的直径和长度 (18)

3.2.3 曲柄 (19)

3.2.4 平衡重 (19)

3.2.5 油孔的位置和尺寸 (19)