A Pseudo-3D Model for Electromagnetic Acoustic Transducers (EMATs)

Previous methods for modelling Rayleigh waves produced by a meander-line-coil electromagnetic acoustic transducer (EMAT) consisted mostly of two-dimensional (2D) simulations that focussed on the vertical plane of the material. This paper presents a pseudo-three-dimensional (3D) model that extends the simulation space to both vertical and horizontal planes. For the vertical plane, we combines analytical and finite-difference time-domain (FDTD) methods to model Rayleigh waves’ propagation within an aluminium plate and their scattering behaviours by cracks. For the horizontal surface plane, we employ an analytical method to investigate the radiation pattern of Rayleigh waves at various depths. The experimental results suggest that the models and the modelling techniques are valid.

[1]  N. A. Haskell.  Radiation pattern of Rayleigh waves from a fault of arbitrary dip and direction of motion in a homogeneous medium , 1962 .

[2]  Lei Kang,et al.  Enhancement of signal amplitude of surface wave EMATs based on 3-D simulation analysis and orthogonal test method , 2013 .

[3]  Gui Yun Tian,et al.  Dual EMAT and PEC non-contact probe: applications to defect testing , 2006 .

[4]  Lei Kang,et al.  3-D modeling and analysis of meander-line-coil surface wave EMATs , 2012 .

[5]  S. Dixon,et al.  Non‐Contact Ultrasonic Characterization of Defects Using EMATs , 2005 .

[6]  Wuliang Yin,et al.  Simultaneous measurement of distance and thickness of a thin metal plate with an electromagnetic sensor using a simplified model , 2003, IEEE Transactions on Instrumentation and Measurement.

[7]  Krishnan Balasubramaniam,et al.  A hybrid finite element model for simulation of electromagnetic acoustic transducer (EMAT) based plate waves , 2010 .

[8]  K. Grattan,et al.  A model for pulsed Rayleigh wave and optimal EMAT design , 2006 .

[9]  C. Dodd,et al.  ANALYTICAL SOLUTIONS TO EDDY--CURRENT PROBE COIL PROBLEMS. , 1968 .

[10]  Kenneth T. V. Grattan,et al.  Electromagnetic acoustic transducers for in- and out-of plane ultrasonic wave detection , 2008 .

[11]  Wuliang Yin,et al.  A multi-frequency impedance analysing instrument for eddy current testing , 2006 .

[12]  Fereidoon Delfanian,et al.  Ultrasonic phased array techniques for composite material evaluation , 2013 .

[13]  Zenghua Liu,et al.  Directivity analysis of meander‐line‐coil EMATs with a wholly analytical method , 2017, Ultrasonics.

[14]  Krishnan Balasubramaniam,et al.  A two-stage finite element model of a meander coil electromagnetic acoustic transducer transmitter , 2011 .

[15]  Zenghua Liu,et al.  Simulation of ultrasonic and EMAT arrays using FEM and FDTD. , 2016, Ultrasonics.

[16]  N. A. Haskell.  Radiation pattern of surface waves from point sources in a multi-layered medium , 1964 .

[17]  S B Palmer,et al.  High accuracy non-contact ultrasonic thickness gauging of aluminium sheet using electromagnetic acoustic transducers. , 2001, Ultrasonics.

[18]  V. Pouget,et al.  Pulsed-Laser Testing for Single-Event Effects Investigations , 2013, IEEE Transactions on Nuclear Science.

[19]  Zenghua Liu,et al.  A wholly analytical method for the simulation of an electromagnetic acoustic transducer array , 2016 .