Leslie M. James
Fred G. Geil
Sonar Engineering Group, Westinghouse Electric Corp., P.O. Box 1488, Annapolis, MD 21146
The underwater acoustic test facility at Westinghouse contains a weather-independent 50-ft-diam, 30-ft-deep redwood tank decoupled from the ground and supported on vibration isolators. Two independent test systems with separate water accesses can accommodate transducers up to 3 tons. The primary test system consists of a Digital MINC/DECLAB-23 processor interfacing to a Hewlett Packard frequency synthesizer and network analyzer. A newer test system consists of a Real Time Systems (RTS)/HP Series 9000 computer-based data acquisition system that has improved low frequency and data storage capabilities; emulating the Naval Underwater Warfare Center system in Newport, RI, but with special application software. The facility is calibrated for pulsed measurements from 200 Hz to 2 MHz. There are several power amplifiers available including an Instruments, Inc. 16.5-kVA amplifier. There are custom test fixtures for torpedo noses, imaging scanners, and other applications as needed, including an 18-in.-diam pressure vessel with an acoustically transparent dome capable of static pressures of up to 120 psi used for high power testing. Scientific Atlanta rotators with digital synchroposition indicators enable accurate plotting of narrow beam patterns and patterns with deep nulls. The work currently in progress is the addition of low-frequency acoustic intensity that will be used for radiated noise measurements.