【作者】 于洪亮；

【导师】 段树林；

【作者基本信息】 大连海事大学 ， 轮机工程， 2009， 硕士

【摘要】 本文通过运用ANSYS有限元法与AVL-EXCITE多体动力学仿真相结合的方法,对船舶柴油机曲轴轴系进行动力学分析仿真。建立合理的柴油机曲轴轴系有限元模型和多体动力学模型,完成船舶柴油机曲轴轴系在一个工作周期内的仿真,得到主轴承和曲轴在实际工作周期内所表现出的动力响应特性,然后对仿真结果进行分析,最后运用有限元分析软件对曲轴进行瞬态动力学分析。首先根据船舶柴油机轴系的结构特点来决定曲轴轴系模型的简化程度,并依据多体动力学模型的需要先建立了轴系缩减有限元模型,在此基础上建立了轴系多体动力学分析模型。接着通过EXCITE多体动力学仿真,进行了柴油机额定转速下的正常工况下包括曲柄销受力、曲轴位移量、转速波动等参数的多体动力学分析,得到曲轴在实际工作周期内所表现出的动力响应特性,进一步验证多体动力学模型的正确性。同时进行主轴承载荷分析,得到最小油膜厚度、最大油膜压力、主轴承轴心轨迹等,对主轴承工作状况下的润滑特性进行分析。最后建立曲轴的精细模型对曲轴进行应力分析。本文所采用的非线性多体动力学与三维实体有限元法避开了传统分析中对于曲轴轴系动态加载条件处理的复杂过程,大幅度的提升了对于船舶柴油机轴系在动载荷作用下各个零部件动态响应分析的精度,同时也为船舶柴油机曲轴的创新设计,改型设计及优化设计提供了强有力的技术支持。更多还原

【Abstract】 A method that combined ansys fmite element method with avl-excite multi-body dynamic simulation is applied to carry on dynamics analysis simulation on the marine diesel engine crankshaft system in this article.Establishes reasonable diesel engine crankshaft system dynamics model,completes the simulation in an action cycle,and obtains the power response characteristic which displays in one operation cycle.Then it carries on the lubrication analysis of main bearing and the transient dynamics analysis on crankshaft using finite element analysis software.First,in view of the concrete product unique features as well as the following functional analysis characteristic simplify the crankshaft system.Then shafting condensed models used for the following multi-body dynamics model are established,and the multi-body dynamics model is also created.According to the results of avl-excite multi-body dynamics simulation, the multi-body dynamics analysis of the diesel engine shafting,which consists of crank force, shafting displacement,speed motion and so on,is implemented.Obtaining the power response characteristic which displays in one operation cycle proves the multi-body dynamics model reasonable further.Simultaneously carries on the bearing load analysis,and obtains the minimum oil film thickness,the peak oil film pressure,orbital path of main bearings and so on.The lubrication condition of main bearings is analyzed.Last,it carries on the transient analysis of the crankshaft.The nonlinear multi-body dynamics and 3D finite element method used to bypass the traditional analysis of dynamic loading conditions for the deal with the complexity of the process,substantially increasing the dynamic response analysis of precision parts under the dynamic load.The method has provided the powerful technical guarantee for the innovation design,the modification design and the optimized design of marine diesel crankshaft.更多还原