Numerical and experimental pressure determination in the very near field of a piezoelectric transducer

• Autorzy: Filipczyński L. , Kujawska T. , Wójcik J. , Tymkiewicz R.
• Języki publikacji: EN

Abstrakty

EN

Measurements in the very near field of piezoelectric transducers are fundamental for many ultrasonic problems. In such cases also the transducer vibrations should be known to perform mathematical models of radiated beams. Acoustic pressure measurements near to the transducer surface can give the necessary information. The pressure of the radiated wave at the transducer surface corresponds to its normal vibration velocity multiplied by the ?c value of the medium. However, this is valid only for the central wave, when the edge wave of the transducer can be ignored. On the other hand, pressure measurements on and very near to the transducer surface are not possible because of the voltage leakage between the electronic transmitter and the PVDF hydrophone used in such measurements. By means of a numerical model, central and edge waves were found for a plane PZT transducer 7.5mm in radius, with the applied 2.7MHz voltage pulse composed of 3 cycles. Two types of boundary conditions of Dirichlet and Neumann were considered showing a negligible difference in the case of short pulses. Basing on numerical and experimental results, practical conditions were determined which make it possible to carry out pressure measurements in the very near field of the transducer, and hence to determine the transducer vibrations which are important for modeling ultrasonic pulse beams.

• Wydawca: Instytut Podstawowych Problemów Techniki PAN ; Komitet Akustyki PAN ; Polskie Towarzystwo Akustyczne
• Czasopismo: Archives of Acoustics
• Rocznik: 2001
• Tom: Vol. 26, no. 3
• Strony: 223--233
• Opis fizyczny: Bibliogr. 11 poz., rys.

Twórcy

autor

Filipczyński L.

• Polish Academy of Sciences Institute of Fundamental Technological Research

autor

Kujawska T.

• Polish Academy of Sciences Institute of Fundamental Technological Research

autor

Wójcik J.

• Polish Academy of Sciences Institute of Fundamental Technological Research

autor

Tymkiewicz R.

• Polish Academy of Sciences Institute of Fundamental Technological Research

Bibliografia

• 1. M. Averkiou and M. Hamilton, Nonlinear distortion of short pulses radiated by plane and focused circular pistons, J. Acoust. Soc. Am., 102, 2539-2547 (1997).
• 2. L. Filipczyński, J. Wójcik, T. Kujawska, G. Łypacewicz, R. Tymkiewicz and B. Zienkiewicz, Nonlinear native propagation effects of diagnostic ultrasound computed and measured in blood, Ultrasound in Medicine and Biology, 27, 2, 251-257 (2001).
• 3. R. Grimsehl Tomaschek, Lehrbuch der Physik, Teubner, Berlin 1942, Vol. 1, pp. 387-388, Vol. 2, pp. 588-589.
• 4. D. Hutchins and G. Hayward, Radiated fields of ultrasonic transducers, [in:] Physical Acoustics, vol. XIX, R. Thurston and A. Pierce [Eds.], Academic Press, Boston, London 1990, pp. 1-80.
• 5. S. Kramer, S. McBride, H. Mair and D. Hutchins, Characteristics of wide-band planar ultrasonic transducers using plane and edge wave contributions, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 35, 253-263 (1988).
• 6. G.Łypacewicz and L. Filipczyński, Measurement method and experimental study of ceramic transducer vibrations, Acustica, 24, 216-221 (1977).
• 7. I. Malecki, Physical foundations of technical acoustics, Pergamon Press, Oxford and PWN, Warsaw 1969, p. 26.
• 8. P. Morse and H. Feshbach, Methods of theoretical physics, McGraw Hill, New York 1953, pp. 495, 679.
• 9. A. Petykiewicz, Wave optics [in Polish], Wydawnictwa Politechniki Warszawskiej, Warsaw 1980, pp. 121-126.
• 10. R. Stephens and A. Bate, Acoustics and vibrational physics, Arnold Publishers, London 1966, p. 141.
• 11. A. Rubinowicz, Selected papers, PWN, Warsaw 1975, pp. 462-463.