Numerical Analysis on the Signal Characteristics for Scattered Far-field of Ultrasonic SH-Wave by the Internal Cavity

재료내 기공결함에 의한 SH형 초음파 원거리 산란장의 신호특성에 대한 수치해석

  • Published : 2000.01.01


In this study, the scattered far-field due to a cavity embedded in infinite media subjected to the incident SH-wave was calculated by the boundary element method. The effects of cavity shape and distance between internal cavity and internal point in infinite media were considered. The scattered far-field of the frequency domain was transformed into the signal of the time domain by using the Inverse Fast Fourier Transform(IFFT). It was found that the amplitude of scattered signal in time domain decreased with the increase of the distance between the detecting points of ultrasonic scattered field and the center of internal cavity in media. In addition, the time delay was clearly found in time domain waveform as the distance between the detecting points of ultrasonic scattered field and the center of internal cavity was gradually increased.


Nondestructive Evaluation;Cavity;Elastodynamic Boundary Element Method;Inverse Fast Fourier Transform;Reflection Factor;SH-Wave


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