ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

5pPAa4. Forward and backward projection of transient acoustic field functions obtained from schlieren and fiber-optic measurements.

Jie Sun

Peter R. Stepanishen

Dept. of Ocean Eng., Univ. of Rhode Island, Kingston, RI 02881

Gregory Clement

Ruiming Liu

Stephen V. Letcher

Univ. of Rhode Island, Kingston, RI 02881

A combination of a schlieren system and a polarimetric fiber-optic detection system is used to obtain line integrals of transient acoustic fields a distance z in front of a planar source. The x,y dependence is obtained from a tomographic reconstruction algorithm. The signal is then forward projected away from the source or back-projected toward the source using wave vector/time domain and frequency methods. Numerical results will be presented to illustrate the projection methods for a number of different transient signals from planar sources with separable and nonseparable space/time velocity distributions. Experimental results for selected source distributions from pulsed ultrasonic transducers will then be presented and discussed.