船用柴油机曲柄连杆机构与机体非线性耦合的数值仿真

Numerical simulation of connecting-rod mechanism coupled nonlinearly with engine block on marine diesel engine

为获得柴油机各部件应力分析和机体结构噪声分析的准确边界条件,利用子结构有限元方法,把曲轴、机体等部件缩减柔性化,通过弹性液体动力润滑和非线性弹簧-阻尼连接把各体单元耦合在一起,进行曲柄连杆机构的柔性多体动力分析,获得十字头滑块处侧推力、主轴承载荷、机体表面响应等数据,其结果可用于曲柄连杆机构和机体的瞬态强度、疲劳、振动分析,柴油机结构噪声和初步的轴承润滑分析.结果表明,该方法可用于曲柄连杆机构与整个机体之间相互影响的研究.

To get the accurate boundary conditions of stress analysis of all components about diesel engine and structure borne noise analysis of engine block,the components of crankshaft and engine block were reduced by sub-structure finite element method and coupled by elastohydrodynamic lubrication and non-linear spring-damper connection.Analysis of flexible multi-body dynamics was performed,and the data of thrust force of crosshead glides,main bearing＇s load and response of block surface etc.were obtained.The results can be used to analyze transient intensity,fatigue,vibration of connecting-rod mechanism and engine block,structure borne noise of engine block as well as primary lubrication of bearings.It shows that the method can be used to study the interaction between the connecting rod mechanism and the whole engine block.