Juan I. Arvelo
Alliant Techsystems, Inc., Arlington, VA 22209
Catholic Univ. of America, Washington, DC 20064
A series of model tank measurements carried out by Glegg et al. at Florida Atlantic University (FAU) has furnished data for range-independent and for downslope sound propagation over consolidated bottom sediments simulating the ocean floor. The modeled ocean floor consisted of an epoxy layer over a semi-infinite concrete basement. The measured range-independent transmission loss is compared here against predicted results from a fast-field propagation model, a normal-mode propagation model, and a parabolic-equation propagation model at frequencies of 15, 20, 25, and 30 kHz. The measured downslope transmission loss is compared against predicted results from the normal-mode and the parabolic-equation models at frequencies of 15, 20, and 30 kHz. The three models were selected for their treatment of bottom elasticity which cannot be neglected in such a hard-bottom case. Mode coupling did not seem to be a significant contributor to sound propagation in the 5-deg downslope case. These comparisons show some unexpected agreement between models and against the measured data in a controlled environment.