Abstract:
Sonar transducers and related components mounted on the hulls of ships and submarines are subject to both inertial shock and acoustic pressure shock when a weapon explodes in the water near the vessel. Consequently, sonar transducers are required to pass an open-water explosive shock test using the floating shock platform (FSP) as specified in MIL-S-901D(NAVY). These tests are expensive, infrequent, and susceptible to erroneous results due to damage incurred in shipment of the transducers between the shock test site and the acoustic calibration facility. This paper describes the development of a conical shock tube (CST) facility at NUWC-USRD that is an inexpensive, rapid-turnaround alternative to open-water testing. CST tests are performed indoors in a closed, water-filled tube with a 25-cm-diam muzzle opening. The CST matches the peak pressures observed in the FSP test using only several grams of explosive. It also matches the axial motion experienced by the FSP in open-water tests. Both design criteria and experimental results are presented. [Work supported by NAVSEA.]