目录1绪论...................................................................11.1本课题的目的及意义...................................................11.2国内外研究的现状与发展趋势...........................................11.2.1曲轴结构设计的发展.................................................11.2.2曲轴强度计算发展...................................................21.3有限元分析...........................................................321015柴油机曲轴结构设计.................................................42.1曲轴的结构...........................................................42.2曲轴的疲劳损坏形式...................................................52.2.1弯曲疲劳裂纹.......................................................62.2.2扭转疲劳裂纹.......................................................62.2.3弯曲--扭转疲劳裂纹.................................................62.3曲轴的设计要求.......................................................72.4曲轴的结构型式.......................................................72.5曲轴的材料...........................................................82.6曲轴的主要部件设计...................................................82.6.1主轴颈和曲柄销.....................................................82.6.2曲柄臂.............................................................92.6.3曲轴圆角..........................................................102.6.4润滑油道..........................................................112.6.5平衡重............................................................122.6.6曲轴两端和轴向止推................................................122.6.7曲轴的强化........................................................132.7曲轴的强度校核......................................................142.7.1曲柄销应力........................................................142.7.2圆角形状系数......................................................172.7.3安全系数..........................................................193有限元分析............................................................213.1ANSYS软件介绍.......................................................21第I页共II页3.2整体曲轴有限元模型的建立............................................223.2.1有限元网格的划分..................................................223.2.2载荷状况的确定....................................................223.3曲轴整体模型计算结果分析............................................243.3.1压应力分析........................................................243.3.2拉应力分析........................................................253.4疲劳强度校核........................................................263.5结论................................................................264总结..................................................................26参考文献.................................................................28致谢.....................................................................32第II页共II页1绪论1.1本课题的目的及意义柴油机与汽油机相比其燃料、可燃混合气的形成以及点火方式都不相同,而柴油机采用压缩空气的办法提高空气温度【1】,因此柴油机的功率更大、经济性能更好,这也导致柴油机工作压力大,要求各有关零件具有较高的结构强度和刚度,所以柴油机比较笨重,体积较大;柴油机的喷油泵与喷嘴制造精度要求高【2】,所以成本较高;另外,柴油机工作粗暴,振动噪声大;柴油不易蒸发,冬季冷车...