Single burst acoustic streaming

• Autorzy: Pedersen G. , Hobćk H.
• Języki publikacji: EN

Abstrakty

EN

On a previous occasion we reported observations of a new type of acoustic streaming which only occurred around a needle hydrophone positioned near the focus of a focusing ultrasound transducer. The streaming was observed even at burst repetition frequencies as low as l Hz. In an attempt to find the origin of this streaming attention was focused on possible excitation of evanescent waves on the probe surface. Presently we report results front a new experiment on this subject. Streaming was observed and measured using tiny tracer particles of polyamid which were recorded with a CCD-video camera and a frame grabber in a PC. The frames were analysed with a Matlab-program for obtaining stream lines and velocity measurements in a vertical plane through the sound axis. The results show that we also observe streaming in free field when using burst repetition frequencies lower than l Hz, and even when using single bursts.

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 2001
• Tom: Vol. 4
• Strony: 197--200
• Opis fizyczny: Bibliogr. 2 poz., rys.

Twórcy

autor

Pedersen G.

• Department of Physics, University of Bergen, Allegt, 55, N-5007, Bergen, Norway

autor

Hobćk H.

• Department of Physics, University of Bergen, Allegt, 55, N-5007, Bergen, Norway

Bibliografia

• 1. T. Berge and H. Hobćk: In Nonlinear Acoustics in the Tum of the Millennium. Proceedings of the ISNA 15,11 W. Lauterborn and T. Kurz (ed.) 2000, pp. 231-234.
• 2. J. K. Sveen: An introduction to MatPIV v, 1.4 (www.math.uio.no/~jks/matpiv/). Department of Mathematics, University of Oslo. (2000).