F170风冷柴油机气缸套热负荷分析

【作者】 丁晓亮；

【导师】 孙平；

【作者基本信息】 江苏大学 ， 动力及机械工程， 2005， 硕士

【摘要】 与水冷柴油机相比,风冷柴油机具有结构简单、热效率高、起动方便、对环境适应性强、以及易于维护等优点,在小功率柴油机上得到广泛应用。但由于冷却空气散热能力差,导致风冷柴油机的热负荷较高,难以强化,热负荷故障率高。因此,改进风冷柴油机冷却系统设计,优化受热零件结构参数,降低热负荷具有重要意义。 本文以F170风冷柴油机热负荷为研究对象,利用热电偶测温技术,对不同冷却系统设计和零件结构方案的受热零件温度场进行了测量。分析了气缸套散热片设计,材料和冷却风扇对温度场的影响。同时还测量了柴油机的工作过程示功图,并以此为基础确定了气缸套的传热边界条件,利用有限元分析软件ANSYS,对气缸套进行数学建模,系统地探讨了有限元法在风冷柴油机缸套设计中的应用,深入研究了风冷柴油机热负荷对性能和可靠性的影响,内容涉及到结构强度、刚度、温度场、热应力、热变形等方面。为了提出最佳改进方案,本文首次采用结构参数化设计的方法,从而得出给定条件范围内的最佳结构参数。更多还原

【Abstract】 Compared with water-cooled diesel engine, air-cooled diesel engine has its particular virtues such as simpler structure, higher efficiency, easier cold-starting, higher adaptability and easier maintenance. For these reasons, it has been widely used in small power diesel engine. The lower cooling efficiency of the air, however, leads to the higher thermal load , more difficult to be strengthened and more likely to be failed due to high thermal load. Therefore, it is important to modify the cooling system and optimize the structure parameter of air-cooled diesel engine.The thermal load of F170 air-cooled diesel engine are investigated by using of the thermocouples to measure temperature field of the heated parts’ in different cooling system and different structure parameter. The effects to the cylinder block thermal load of the cylinder’s design, the material and the cooling fan are analyzed. In the same time, according to the measured indicator diagram of the cylinder pressure in the engine, the heat transfer boundary of the cylinder block has been calculated. By usinga FEM (Finite Element Method) software-ANSYS, the mathematic model areestablished. The application of FEM to structure design of the cylinder block of air-cooled diesel engine are studied systematically. This FEM involved strength, stiffness, temperature field, thermal stress field, thermal deformation and so on. In order to optimization of the structure design, The APDL (ANSYS Parametric Design Language) method are introduced to optimize the structure parameter.更多还原