A method for calculating the dispersion of guided waves in pipe
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摘要: 为了求得管道中导波的频散特性,提出了一种基于有限元的模式分析法来求解频散关系。以导波理论为基础,构建了Navier-stokes方程,采用分离变量法得到Helmholtz方程及泛函形式,并利用COMSOL软件对Helmholtz方程进行特征值的求解,计算结果与半解析有限元法所求得的结果基本吻合,并且能够求解出环状模态,证明了该方法的有效性及求解的全面性。同时,运用导波理论及铁木辛柯梁理论对低频的频散关系进行理论求解,通过对比,验证了模式分析法的精度良好。最后通过位移分量分析了模态的特征,为管道导波无损检测提供了依据。Abstract: A finite element based mode analysis method is proposed to solve the dispersion relations. Based on the guided wave theory, the Navier stokes equation is constructed. The Helmholtz equation and functional form are obtained by using the variable separation method and solved by the finite element method. The calculated results are basically consistent with the results obtained by the semi-analytical finite element method, and the ring modal can be gotten, which proves the effectiveness and comprehensiveness of this method. At the same time, the guided wave theory and the Timoshenko Beam theory are applied to theoretically solve the dispersion relations of low frequency, which shows the characteristics of the modal analysis method are superior. Finally, the modal characteristics are analyzed by the displacement component, which provides a basis for the mode selection of guided wave on nondestructive testing.
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Keywords:
- pipe /
- guided wave testing /
- dispersion /
- finite element /
- mode analysis
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[1] 贾志绚, 张潇, 赵星,等. 基于弹性波法的公路护栏立柱埋深无损检测技术及影响因素研究[J]. 北京工业大学学报, 2012, 38(6):870-874. [2] LONG R, CAWLEY P, LOWE M. Acoustic wave propagation in buried iron water pipes[J]. Proceedings Mathematical Physical & Engineering Sciences, 2003, 459(2039):2749-2770.
[3] LOWE M J S, CAWLEY P, PAVLAKOVIC B N. A general purpose computer model for calculating elastic waveguide properties, with application to non- destructive testing[C]//Surface Waves in Anisotropic and Laminated Bodies and Defects Detection. Dordrecht:Kluwer Academic Publishers, 2004:241-256.
[4] SECO F, JIMÉNEZ A R. Modelling the generation and propagation of ultrasonic signals in cylindrical waveguides[M]. London:InTech Open Access Publisher, 2012:1-28.
[5] 何存富, 王学浦, 王秀彦,等. 基于导波技术的高速公路护栏立柱埋深检测[J]. 中国公路学报, 2008, 21(6):37-42. [6] BOCCHINI P, MARZANI A, VIOLA E. Graphical user interface for guided acoustic waves[J]. Journal of Computing in Civil Engineering, 2011, 25(3):202-210.
[7] 胡剑虹, 唐志峰, 吕福在,等. 复合管道轴对称导波改进半解析有限元建模[J]. 浙江大学学报(工学版), 2015, 49(1):116-122. [8] 朱龙翔, 王悦民, 宗侣,等. 基于模态分析方法的管道导波频散曲线计算[J]. 海军工程大学学报, 2014(6):64-68. [9] 王悦民, 杨波. 磁致伸缩导波无损检测理论与方法[M]. 北京:科学出版社, 2015. [10] 孙灵芳, 徐曼菲, 朴亨,等. 基于流固耦合的换热管道污垢超声回波检测数值模拟与实验[J]. 中国机械工程, 2017, 28(3):340-348. [11] 鄂林仲阳, 杜强, 李上明. 基于谱元法的空间刚架动力学特性分析[J]. 计算力学学报, 2016, 33(5):802-806. [12] COWPER G R. The shear coefficients in Timoshenko's beam theory[J]. Journal of Applied Mechanics, 1966, 33(2):335-340.
[13] ALLAEI D, SOEDEL W, YANG T Y. Natural frequencies and modes of rings that deviate from perfect axisymmetry[J]. Journal of Sound & Vibration, 1986, 111(1):9-27.
[14] 徐进友, 刘建平, 王世宇,等. 环状旋转周期结构模态摄动分析[J]. 天津大学学报(自然科学与工程技术版), 2010, 43(11):1015-1019. [15] 何存富, 郑明方, 吕炎,等. 超声导波检测技术的发展、应用与挑战[J]. 仪器仪表学报, 2016, 37(8):1713-1735.
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