【作者】 王志勇；

【导师】 孙丽萍； 杨英；

【作者基本信息】 大连交通大学 ， 车辆工程， 2005， 硕士

【摘要】 在简述研究柴油机活塞尤其是组合活塞接触问题重要性的前提下，给出了研究本课题的重点、难点及详细的实现方法。以力学和有限元法理论为基础，通过借助大型CAD／CAE软件I-DEAS和MSC．Marc，实现了不同软件间的分工协作。对16V240ZJ型柴油机钢顶铝裙组合活塞建立了基于活塞顶、活塞裙、连接螺栓以及活塞销的多体接触模型，通过稳态热传导分析实现了关键点温度与实测温度的任意逼近，较准确地模拟出了该组合活塞的温度分布。针对柴油机在实际应用过程中的各种情况，确立了活塞的典型工况，分别进行了预紧工况、最大自然压缩工况、最大自然拉伸工况、最大温度压缩工况和最大温度拉伸工况的计算，成功地解决了预紧力加载的难题。最后，得到了该组合活塞详细的温度场、应力场和应变场，并根据计算结果对模型的几个接触面进行了详细的分析，得到了一些有用的结论。 考虑到活塞温度场数值模拟过程中，施加第三类边界条件时通常需要反复修正换热系数，这个过程操作繁琐，并且带有一定的盲目性，工作量大。为此，本文利用坐标轮换法并引入灵敏度分析，指导换热系数的调整方向和幅度；通过编制程序，结合有限元软件MSC．Marc，首次实现换热系数的自动搜索，提高了求解效率。该方法免除了繁琐的人工调整，大大地提高了工作效率。更多还原

【Abstract】 On the precondition of a brief depiction on the importance of the contact problem study of the diesel piston, especially composite piston, educes the keystone, difficulty and detailed operation method of this subject. On the basis of the mechanics and FEM theory, depending on the CAD/CAE software I-DEAS and MSC.Marc, realizes the cooperation between the difference softwares. By building the multi-contact model, which is base on the crown, skirt, connect bolt and piston pin of the 16V240ZJ diesel composite piston with steel crown and aluminum shirt, realizes the arbitrary approach of the computing and testing temperature on the key point by the static heat transfer analysis, and exactly simulates the temperature distribution of the composite piston. Aiming at the different situations of the diesel in practice using, establishes the typical load cases of the piston, respectively computes the preload load case, the most normal compress load case, the most normal draught load case, the most temperature compress load case and the most temperature draught load case, and successfully resolves the difficulty of the preload. At the end, gains the particular temperature field, stress field and deformation field, analyzes several contact surfaces of the model in detail by using the computing results, and obtains some useful conclusions.During the numerical simulation of the temperature field in pistons, usually applying the third kind of boundary condition needs correct the heat transfer coefficient repeatedly. The operating process is boring and blind, and the workload is large. Therefore, the paper uses the coordinate alternation method and the sensitivity analyses to guide the adjusting direction and range of the heat transfer coefficient. By compiling programs, integrating the FEA software MSC.Marc, gets the automatic search of the heat transfer coefficient and improves the solution efficiency. The method avoids the boring adjustment by hand and increases the work efficiency greatly.更多还原