Beschreibung:
<jats:p>To apply the Biot theory to the study of the interaction of acoustic waves with ocean sediments, the coefficients in the equations must be evaluated. The coefficients depend on the frequency and the fabric, or microstructure, of the sediments. A method for evaluating the drag and virtual mass coefficients has recently been developed [A. Bedford et al., J. Acoust. Soc. Am. 76, 1804–1809 (1984)]. The method requires solving for the motion of the fluid in the pores when the solid constituent is subjected to a spatially uniform, oscillatory motion. The finite element method has been used to determine the fluid motion. The drag and virtual mass coefficients have been determined for a variety of two-dimensional pore geometries. It was found that the drag coefficient is insensitive to the pore geometry, while the virtual mass coefficient is very sensitive to the pore geometry. It was determined that the coefficients are independent of the frequency up to a characteristic value of dimensionless frequency and exhibit a bilinear dependence on frequency. [Work supported by ONR.]</jats:p>