饲草揉碎机转子模态分析及结构优化  

Modal Analysis and Structure Optimization of the Rotors of Forage Rubbing and Breaking Machines

作　　者：王金博[1] 董海军 翟之平[1] 程海鹰[1] 康小云[1] 吴雅梅[3] WANG Jinbo;DONG Haijun;ZHAI Zhiping;CHENG Haiying;KANG Xiaoyun;WU Yamei(College of Mechanical Engineering,Inner Mongolia University of Technology,Huhhot 010010,China;Agriculture and Animal Husbandry Bureau of Chifeng,Chifeng 024000,Inner Mongolia China;Huhhot Branch of Chinese Academy of Agricultural Mechanization Sciences,Huhhot 010020,China)

机构地区：[1]内蒙古工业大学机械学院,呼和浩特010051 [2]赤峰市农牧局,内蒙古赤峰024000 [3]中国农业机械化科学研究院呼和浩特分院,呼和浩特010020

出　　处：《噪声与振动控制》2018年第5期52-56,61,共6页Noise and Vibration Control

基　　金：国家自然科学基金资助项目(102-413069);内蒙古自然科学基金资助项目(102-413111);内蒙古自然科学基金资助项目(2018MS05059)

摘　　要：针对目前饲草揉碎机转子工作时存在振动、噪声大的问题,为避免发生共振,采用理论分析和有限元仿真方法对转子自由模态进行计算,并通过模态试验对理论分析和数值计算结果进行验证。在此基础上,采用流固耦合方法对转子进行预应力模态分析。对转子进行共振分析发现激振频率与转子低阶频率较接近,极易发生共振,为增大激振频率和转子低阶频率避开率,基于响应面法对影响转子振动特性的结构参数进行优化。分析结果表明:预应力对转子的前3阶模态影响较大,频率分别提高了14.01%、12.01%以及10.54%;锤架板厚度对转子第1阶频率影响较大,主轴直径次之,锤架板直径影响最小;优化后频率避开率由原来的5.03%增大为20.83%,避免了共振的发生,且转子强度和刚度均满足使用要求。At present,vibration and noise of the rotors of forage rubbing and breaking machines become a serious problem.In this paper,the theoretical analysis and finite element simulation are used to calculate the free modals of the rotors,and a modal test is carried out to verify the theoretical analysis and the numerical calculation method.On this basis,prestressed modal analysis of the rotor is carried out by using the fluid-solid coupling method.The analysis of the rotor shows that the excitation frequency is close to a lower order frequency of the rotor,which can cause resonance very easily.In order to increase the excitation frequency to avoid from the low frequency of the rotor,the structural parameters which affect the vibration characteristics of the rotor are optimized based on response surface method.The results show that:(1)The prestress has a great impact on the first three order natural frequencies of the rotor,and the first,second and third order frequencies are increased by 14.01%,12.01 and 10.54%respectively;(2)The thickness of the hammering plate has the greatest influence on the first order frequency of the rotor,the diameter of the spindle has the second,and the diameter of the hammering plate has the minimal influence;(3)After the optimization,the frequency avoidance rate is increased from 5.03%to 20.83%and the resonance is effectively avoided.Besides,the strength and stiffness of the rotor can meet the requirements of use.

关 键 词：振动与波 揉碎机转子 模态分析 模态试验 响应面优化 

分 类 号：TH113.1[机械工程—机械设计及理论]