冲击荷载下输液管道动响应分析的谱单元方法  

Dynamic analysis of pipe conveying fluid under impact load with spectral element method

作　　者：李宝辉[1] 景丽娜 王正中[1] LI Baohui;JING lina;WANG Zhengzhong(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《振动与冲击》2020年第21期179-185,194,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(51505388);中央高校基本科研业务费专项资金资助(2452020168)。

摘　　要：建立了基于Timoshenko梁的管道轴向流致振动模型,采用谱单元方法分析了管道的动响应。借助离散傅里叶变换,将时域控制方程转换为频域形式,结合有限元法获得了与频率相关的谱单元矩阵,进而发展出分析管道在冲击荷载作用下的动响应计算方法。通过管道固有频率和Timoshenko梁动响应的对比计算,验证了该方法的有效性。最后,采用谱单元法计算了管道在不同流速、不同瞬态荷载作用下的动响应。结果显示,谱单元法并且只需两个单元就可以分析管道的动响应并且具有很高精度。Here, a pipe axial flow-induced vibration model was built based on Timoshenko beam, and the spectral element method(SEM) was applied in dynamic response analysis of a pipe conveying fluid. By means of discrete Fourier transformation, the pipe’s dynamic equations in time domain were converted into those in frequency domain. Being similar to the finite element method(FEM), the spectral element matrix equation was obtained. Then, the computation method was developed for dynamic response of pipe conveying fluid under point impact loads. The natural frequencies and dynamic responses of the pipe conveying fluid were computed with SEM, and the results were compared with those published in literature to verify the effectiveness of SEM. Finally, the pipe’s dynamic responses were computed using SEM under different fluid flow velocities and transient impact loads. Results showed that the proposed SEM has a high accuracy;only two spectral elements are needed to analyze dynamic responses of a pipe conveying fluid under point impact loads.

关 键 词：输液管道 谱单元法 动响应 固有频率 

分 类 号：O321[理学—一般力学与力学基础]