三缸内燃泵曲轴负荷多学科仿真研究

Multi-disciplinary simulation study on crankshaft load of three-cylinder internal combustion pump

曲轴是三缸内燃泵的重要运动和功能零件。通过热力学、系统动力学、流体力学分析得到连杆对曲轴的作用力。建立了能真实反映曲轴实际工作状况的全接触有限元分析模型,考虑连杆荷载、重力、角速度、摩擦力,对各缸作功或吸气冲程中曲轴的接触应力、摩擦应力和Von Mises应力进行了计算,第2缸曲柄销应力小于第1缸,第1缸小于第3缸。各种情况下摩擦应力为接触应力的3%左右,最大Von Mises应力发生在主轴颈的过渡圆角处。曲轴疲劳安全系数约为2.85,满足要求。

Crankshaft is an important moving and functional part of three-cylinder internal combustion pump.The force applied on crankshaft by connecting-rod was obtained through thermodynamics,system dynamics and hydrodynamics analysis.The full contact finite element model of crankshaft which can reflect the actual conditions was also constructed.By considering the load from connecting-rod,gravity,angular velocity and friction force,the contact stress,friction stress and Von Mises stress of crankshaft during the strokes of power and intake were computed.Altogether,the stress of the second crankpin is less than that of the first,and the first is less than the third;the friction stress is about three percent of that of the contact;the maximum Von Mises stress occurs at the knuckle filleting of crankpin.Fatigue assurance coefficient of crankshaft is about 2.85,which can meet the design requirement.