A Gaussian finite-element method for description of sound diffraction

A new method for solving diffraction problems is presented. It is based on the use of Gaussian diffraction theory. Comparison of the Gaussian beam exp ansion and Fourier series expansion reveals that the Gaussian expansion is a more general and more powerful technique. The new method combines the Gau ssian beam superposition technique [Wen and Breazeale, J. Acoust. Sec. Am. 83, 1752-1756 (1988)] and the numerical (finite-element) solution to the pa rabolic equation [Huang, J. Acoust. Sec. Am. 84, 1405-1413 (1988)]. The new method is capable of solving for the sound field even in an inhomogeneous medium or in the presence of reflection, as shown by computer modeling. The source may be a Gaussian source or a distributed source. Calculated result s are compared with experimental results in a laboratory water lank. (C) 19 99 Acoustical Society of America. [S0001-4966(99)02509-6].