Numerical calculations of ultrasonic fields I: Transducer near fields
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A computer code for the calculation of linear acoustic wave propagation in homogeneous fluid and solid materials has been derived from the thermal-hydraulics code STEALTH. The code uses finite-difference techniques in a two-dimensional mesh made up of arbitrarily shaped quadrilaterals. Problems with two-dimensional plane strain or two-dimensional axial symmetries can be solved. Free, fixed, or stressed boundaries can be used. Transducers can be modeled by time dependent boundary conditions or by moving pistons. This paper gives a brief description of the method and shows the results of the calculation of the near fields of circular flat and focused transducers. These results agree with analytic theory along the axis of symmetry and with other codes that use a Huygens reconstruction technique off-axis.
Key wordsNondestructive evaluation ultrasonic field ultrasonic transducer modeling finite difference
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- 1.R. Hofmann, STEALTH, A Lagrange explicit finite-difference code for solids, structural, and thermohydraulic analysis, EPRI NP-260 (August, 1976).Google Scholar
- 2.J. A. Johnson,Numerical Calculations of Ultrasonic Fields (EGG-IS-5781, February, 1982).Google Scholar
- 3.J. Krautkramer and H. Krautkramer,Ultrasonic Testing of Materials, (Springer-Verlag, New York, 1977), p. 69, Equation (4.4) p. 75, Equation (4.7).Google Scholar
- 4.J. Zemanek, Beam behavior in the near field of a vibrating piston,J. Acoust. Soc. Am. 49:181–191 (1971).Google Scholar
- 5.J. C. Lockwood and J. G. Willette, High-speed method for computing the exact solution for the pressure variations in the nearfield of a baffled piston,J. Acoust. Soc. Am. 53:735–741 (1973).Google Scholar
- 6.W. L. Beaver, Sonic nearfields of a pulsed piston radiator,J. Acoust. Soc. Am. 56:1043–1048 (1974).Google Scholar
- 7.C. P. Griffice and J. A. Seydel, Spherical wave decomposition approach to ultrasonic field calculations,J. Nondestr. Eval. 2:241–247 (1981).Google Scholar
- 8.B. A. Barna, private communication, EG&G Idaho, Inc., Idaho Falls, Idaho, 1982.Google Scholar