Loveday, Philip WLong, Craig S2009-03-102009-03-102007-03Loveday, PW and Long, CS. 2007. Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements. Sensors and Smart Structures Technologies for Civil, Mechanical and Aerospace Systems 2007, San Diego, California, USA, 19-22 March 2007, pp, 109780819466501http://dx.doi.org/10.1117/12.714744http://hdl.handle.net/10204/3199Copyright: 2007 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibitedPiezoelectric transducers are commonly used to excite waves in elastic waveguides such as pipes, rock bolts and rails. While it is possible to simulate the operation of these transducers attached to the waveguide, in the time domain, using conventional finite element methods available in commercial software, these models tend to be very large. An alternative method is to use specially formulated waveguide finite elements (sometimes called Semi-Analytical Finite Elements). Models using these elements require only a two-dimensional finite element mesh of the cross-section of the waveguide. The waveguide finite element model was combined with a conventional 3-D finite element model of the piezoelectric transducer to compute the frequency response of the waveguide. However, it is difficult to experimentally verify such a frequency domain model. Experiments are usually conducted by exciting a transducer, attached to the waveguide, with a short time signal such as a tone-burst and measuring the response at a position along the waveguide before reflections from the ends of the waveguide are encountered. The measured signals are a combination of all the modes that are excited in the waveguide and separating the individual modes of wave propagation is difficult if there are numerous modes present. Instead of converting the measured signals to the frequency domain the authors transform the modelled frequency responses to time domain signals in order to verify the models against experiment. The frequency response was computed at many frequency points and multiplied by the frequency spectrum of the excitation signal, before an inverse Fourier transform was used to transform from the frequency domain to the time domain. The time response of a rail, excited by a rectangular piezoelectric ceramic patch, was computed and found to compare favourably with measurements performed using a laser vibrometer. By using this approach it is possible to determine which modes of propagation dominate the response and to predict the signals that would be obtained at large distances, which cannot be measured in the lab, and would be computationally infeasible using conventional finite element modellingenElastic waveguideFinite element methodPiezoelectric excitationTime domain simulationSPIEConference PresentationLoveday, P. W., & Long, C. S. (2007). Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements. International Society for Optical Engineering (SPIE). http://hdl.handle.net/10204/3199Loveday, Philip W, and Craig S Long. "Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements." (2007): http://hdl.handle.net/10204/3199Loveday PW, Long CS, Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements; International Society for Optical Engineering (SPIE); 2007. http://hdl.handle.net/10204/3199 .TY - Conference Presentation AU - Loveday, Philip W AU - Long, Craig S AB - Piezoelectric transducers are commonly used to excite waves in elastic waveguides such as pipes, rock bolts and rails. While it is possible to simulate the operation of these transducers attached to the waveguide, in the time domain, using conventional finite element methods available in commercial software, these models tend to be very large. An alternative method is to use specially formulated waveguide finite elements (sometimes called Semi-Analytical Finite Elements). Models using these elements require only a two-dimensional finite element mesh of the cross-section of the waveguide. The waveguide finite element model was combined with a conventional 3-D finite element model of the piezoelectric transducer to compute the frequency response of the waveguide. However, it is difficult to experimentally verify such a frequency domain model. Experiments are usually conducted by exciting a transducer, attached to the waveguide, with a short time signal such as a tone-burst and measuring the response at a position along the waveguide before reflections from the ends of the waveguide are encountered. The measured signals are a combination of all the modes that are excited in the waveguide and separating the individual modes of wave propagation is difficult if there are numerous modes present. Instead of converting the measured signals to the frequency domain the authors transform the modelled frequency responses to time domain signals in order to verify the models against experiment. The frequency response was computed at many frequency points and multiplied by the frequency spectrum of the excitation signal, before an inverse Fourier transform was used to transform from the frequency domain to the time domain. The time response of a rail, excited by a rectangular piezoelectric ceramic patch, was computed and found to compare favourably with measurements performed using a laser vibrometer. By using this approach it is possible to determine which modes of propagation dominate the response and to predict the signals that would be obtained at large distances, which cannot be measured in the lab, and would be computationally infeasible using conventional finite element modelling DA - 2007-03 DB - ResearchSpace DO - 10.1117/12.714744 DP - CSIR KW - Elastic waveguide KW - Finite element method KW - Piezoelectric excitation KW - Time domain simulation KW - SPIE LK - https://researchspace.csir.co.za PY - 2007 SM - 9780819466501 T1 - Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements TI - Time domain simulation of piezoelectric excitation of guided waves in rails using waveguide finite elements UR - http://hdl.handle.net/10204/3199 ER -