直列式四缸内燃机系统多体动力分析

Multi-body Dynamic Analysis of In-line Four-cylinder Internal Combustion Engine System

以直列式四缸机构为研究对象,运用内燃机的基本理论对其进行多体动力分析,得出多体系统中机构之间的运动关系,并算出当活塞2上承受燃气力达到最大值σ=5.9 MPa时曲柄2所连曲轴处受到的冲击力为F=340kN。对内燃机系统的刚柔耦合多体动力进行分析,旨在得到系统运转过程中柔性体曲轴上最大应力节点13 230处和最小应力节点35 723处的动应力历程,同时考察最危险节点13 230处及其周围危险区域的强度和稳定性,为后续结构优化提供参考依据。

Take the in-line four-cylinder mechanism as the research object,utilize the basic theory of internal combustion engine to conduct the multi-body dynamic analysis,obtain the movement relationship between each mechanism in the multi-body system,calculate that the impact force in the connection location between crank andcrankshaft when the bearing gas force on the piston 2has reached the maximum valueσ=5.9MPa is F=340kN.The rigid-flexible coupling multi-body analysis of internal combustion engine system is also a emphasis of this research,its purpose is to obtain the dynamic stress histories of maximum stress point 13 230 and minimum stress point 35 723 on the flexible body crankshaft during the system operating process,it also investigates the strength and stability of most dangerous point 13 230 and its surrounding danger zones and provides the reference foundation for subsequent structure optimization.