具有弹性支承的周期性输流直管的振动分析  

Vibration Analysis of Periodic Pipe of Fluid Conveying with Elastic Supports

作　　者：刘伟[1] 万志勇 赵千里 LIU Wei;WAN Zhiyong;ZHAO Qianli(Department of Mechanical Engineering,Changzhou Vocational Institute of Mechatronic Technology,Changzhou 213164,Jiangsu,China;Changzhou Zhixu New Energy Power Technology Co.,Ltd,Changzhou 213164,Jiangsu,China)

机构地区：[1]常州机电职业技术学院机械工程学院,江苏常州213164 [2]常州智戌新能源电力科技有限公司,江苏常州213164

出　　处：《噪声与振动控制》2024年第5期69-74,共6页Noise and Vibration Control

基　　金：江苏省第六期“333高层次人才培养工程”资助项目((2022)3-16-850);江苏省高等学校基础科学(自然科学)研究面上资助项目(22KJD130001);常州市基础研究计划(应用基础研究)资助项目(CJ20220017)。

摘　　要：利用Laplace变换法对修正流动模型的输流直管的流体诱发振动微分方程进行推导,得到位置相关项的解的具体表达式,基于欧拉-伯努利梁理论并经过化简最终导出输流直管的传递矩阵表达式,进一步获得整个管路系统的特征方程。相比于基于波动方法的传递矩阵法,该方法的特征方程仅为2阶,大大节省计算时间。通过与微分变换法对比发现,运用两者计算输流管路固有频率所得结果几乎一致。考虑到制造误差能够导致管路材质不均匀,用周期性来近似描述材质的不均匀性,利用该方法计算具有弹性支承的周期性输流直管的颤振临界流速,发现材质的不均匀段长度越小,结果越接近纯悬臂式输流直管,运用该方法可以优化弹性支承(包括弹性系数和安置位置)和材料特性,可将其推广至复杂结构的输流管路的动态特性研究,其可为设计人员提供精确的计算结果。Laplace transform is used to deduce the modified flow induced vibration differential equation,and therewith position related solution is expressed in a specific form.Based on Euler-Bernoulli beam theory and after elementary transformation,the transfer matrix of the fluid conveying straight pipe is obtained,furthermore the characteristic equation of the whole piping system is gained.Compared with wave approach based transfer matrix method(TMM),the proposed method provides a 2-order characteristic differential equation,which saves lots of computing time.Results of the proposed method are almost the same as those of differential transformation method(DTM)in calculating intrinsic property of fluid conveying pipe.Then,a periodic pipe is introduced to approximate the inhomogeneity of material due to the manufacture errors,critical velocity for flutter of such a pipe with elastic supports is calculated by the proposed method.It is discovered that the smaller the uneven section length of the material is,the closer the result is to the cantilever pipe.The method can be used to optimize elastic supports(including coefficients and installation position)and material properties,and can be generalized to study dynamic problems of complex structures.

关 键 词：振动与波 输流直管 传递矩阵法 LAPLACE变换 临界流速 

分 类 号：O327[理学—一般力学与力学基础] TH113[理学—力学]