Experimental investigation of shock wave propagation in the postfocal region of a focussed sound field

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Authors

  • H. HOBAEK Department of Physics, University of Bergen, Norway

Abstract

This paper reports some experimental results on the postfocal region of the sound field from a curved circular transducer at very high amplitude. It is found that along the axis the shock front seems to propagate with a speed different from the "background sound". This is explained by diffraction: The field may be separated into two main contributions, one from the edge of the source - arriving first and causing the "background sound" - and one from the main region of the source - causing the shock. After being formed the shock propagates with no change in shape, and with uniformly decreasing amplitude. The shock propagation speed seems to increase slightly with source amplitude.

References

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