An investigation into scattering of torsional guided wave in pipes and its inverse problem
Ultrasonic waves are widely used for non-destructive examination of pipes in industrial and infrastructure fields. It is especially useful when the pipes are inaccessible by other approaches. This paper mainly studies the scattering properties of the ultrasonic torsional guided waves passing through the axisymmetric scatterer, and investigates into the possibility whether the scatterer can be reconstructed by data of scattering coefficients. Firstly, the paper discribes how the wave field is calculated by means of boundary element method (BEM), where a 2-Dimensional BEM formation is applied. Secondly, the mode-exciting method is introduced to solve the reflection and transmission coefficients for each guided wave mode. The paper shows that when properly exciting the pipe, the total reflection and transmission wave fields are clearly decomposed into a series of wave modes orthogonal from each other. Finally, the paper proposes a formation of the inverse problem. Simulation results show that the variation for section polar moment of inertia can be reconstructed by reflection coefficients, using the fundamental torsional mode.The abstract must be written in English. It should present novel theory, numerical method or applications related to computational mechanics, computational engineering and sciences, and preferably unpublished at the time of the Conference. Please use * after the name of one author to specify the presenting author. No author will be invited to present more than one paper at the Conference. Abstract is limited in two page and the MSWord file or PDF file should be submitted in the correct format as presented in this file. Please use your two full page to give readers as much information as possible, including few important figures and up to five main references. Too short abstract is not reasonable to be published in the printed volume. The prescribed paper size for the electronic file is A4. Please make sure that the settings in your word processor and PDF-converter are chosen accordingly. Text should be produced within the dimensions shown on this page; total width of 18.2 cm and a maximum length of 26.2 cm. Please keep the headlines before the title line no change. You should start with the title of the paper, all authors with their affiliations, postal and email addresses. The recommended fonts are 12-point fonts for the main body of text, and 18-point font for the title, and the recommended line spacing is single line spacing. These instructions have been produced using Times New Roman fonts. Other recommended fonts are Times Roman. Italics can be used for emphasis in the main body of text.
B.Wang S.Hirose
Department of Civil Engineering,Tokyo Institute of Technology,Tokyo,152-8552 JapanChina Department of Mechanical and Environmental Informatics,Tokyo Institute of Technology,Tokyo,152-8552
国际会议
南京
英文
1-2
2009-10-18（万方平台首次上网日期，不代表论文的发表时间）