Underwater acoustic facilities at AARC

Abstract

Facilities at AARC include an acoustic wind tunnel (AWT), a pressurized pulse tube, and a reverberant water tank. The AWT may also be used as an anechoic room. The AWT was designed primarily for the acoustic evaluation of submersible propulsors. It is large enough to use prototype hardware for an important class of such vehicles. A model afterbody with control surfaces and propulsor is submerged in an open jet surrounded by a large anechoic room. In addition to the low background noise levels and turbulence required for this duty, the AWT has a unique nose-sting model mounting arrangement that avoids the noise and flow disturbances of strut or wire supports. The pulse tube provides measurements of reflection and transmission properties of materials and coating systems samples at submergence pressures to 1000 psi and with controllable temperature. The acoustic water tank provides a highly reverberant facility useful for measurement of radiated power from submerged sources and has been used to measure radiation transfer gains by the application of reciprocity.