NUMERICAL SIMULATION OF PULSED MEANDER COIL EMAT

Electro magnetic acoustic transducers (EMATs) are now being widely investigated for non‐contact non‐destructive testing (NDT) of solid materials. This type of transducer can generate and/or detect ultrasound in electrically conductive or magnetic materials through the Lorentz force principle and/or magneto‐elastic effects. This work describes about the Meander coil EMAT that is modeled using finite element method. A 2‐D finite element model was developed to calculate the induced current inside the medium, and subsequently the Lorentz force density in the medium. The calculated Lorentz force density values are applied for simulating the transient ultrasonic wave generation within the medium. Meander coil EMATs that were designed using the model were used for experimental studies. Several case studies will be reported which include Rayleigh waves, Shear waves, Longitudinal and Lamb wave modes using pulsed mode of excitation. The experimental results were agreed well with the simulation results.