文章编号：10062971(2013)04-002104
大型活塞压缩机曲轴扭振分析（二）
瞬态应力分析
詹科，余宾妻，余小玲，冯全科
（西安交通大学能源与动力工程学院，陕西西安710049）
摘要：介绍了一种结合多保系统动力学和有限元分析对大型活塞压编机曲轴进行瞬态应力计算的方法。该方法首先运用多体动力学方法对曲轴、连杆、活塞等运动部件的动力学过程进行仿真，得到作用在曲轴上的真实载荷，再将此载荷作为边界条件应用到曲轴的有限元模型中，最后求解得到曲轴的瞬时应力。与传统的担振当量系统计算方法，以及单一的曲轴应力有限元分析方法相比，该方法考虑了往复质量的转动惯量随曲柄转角的变化，并能计算曲轴担
转、横向、轴向3个振动方向的综合应力，固而计算结果更为精确。关键词：曲轴；担转振动；变惯量；多体动力学；大型往复式压缩机
中图分类号：TH457
文献标志码：A
设计研究
TorsionalVibrationAnalysisoftheCrankshaftofLargeTypePistonCompressor
TransientStressAnalvsis(II)
ZHAN Ke, YU Bin-yan, YU Xiao-ling,FENG Quan-ke
(School of Energy and Power Engineering,Xi'anJisotong University,Xi'an 710049, China)
Abstract:A new method combined multi-body dynamics theory and finite element analysis was presented to calculate transient stress of the crankshaft of large type piston compressor.Firstly,a simulation on foundation of multi-body dynamics theory was done to get dynamic behaviors of the crankshaft,the connecting rod,the piston and so on,and thus to get the real loads acting on the crankshaft. Then these loads served as the boundary conditions were applied to the finite element model of the crankshaft.Finally,transient stress of the crankshaft is obtained by solving this finite element model.Comparing to traditional methods,such as the equivalent torsional vibration method and the only finite element method for the stress calculation,this new method not only considers the inertia of re ciprocating mass varying with the crank angle,but also can calculate the integrated vibration stress of three directions including tor-sion, lateral and axial.Therefore,the results of the new method will be more precise.
Key words: crankshaft; torsional vibration; variable inertia;multi-body dynamics;large type reciprocating compressor
1
引言
随着石油化工规模的扩大，往复压缩机朝着
大流量、高转速和高压力方向发展，压缩机的列数也随之增加，导致压缩机曲轴的自振频率降低，曲轴有可能因扭转振动而破坏。美国石油学会
收稿日期：2013-06-28
■2013年04期（总第240期）
API618标准规定，当压缩机列数大于6列时，需要对压缩机曲轴进行扭转振动分析[]。本文作者已对大型曲轴模态计算的方法作了介绍[3]，主要介绍曲轴瞬态应力的计算方法。
传统计算曲轴扭振应力的方法是将复杂的实际轴系简化成扭振特性相同的当量系统[3-5]。一方面，
压缝机技术21 Compre