Acoustic Waves Generated by a Laser Line Source on the Surface of a Cylindrical Rod or Cavity
نویسندگان
چکیده
In this work, a model is proposed to predict acoustic waves generated in a homogeneous and isotropic cylindrical cavity by a laser line source. The Fourier series expansion is introduced for one spatial coordinate to solve this transient response problem. Theoretical displacements are obtained for an aluminum cylindrical cavity of internal diameter 40 mm. The corresponding displacements are observed experimentally by the laser ultrasonic technique. For comparison, theoretical and experimental waveforms are also provided for an aluminium cylindrical rod under laser line source excitation. Good agreement is found in the time arrival, shape and relative amplitude of surface acoustic waves. The dispersion of surface acoustic waves is quite different to that on a cylindrical rod.
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