USA

USA, The Underwater Shock Analysis code calculates the transient response of a submerged structure to a spherical shock wave of arbitrary pressure profile and source location. The structure can be totally or partially submerged, and may be linearly elastic, or contain both geometric and material nonlinearities, depending upon the structural code in use. The fluid surrounding the structure is modeled as an infinite or semi-infinite acoustic medium, and the effect of free surface cutoff due to bulk cavitation can be taken into account in USA. The external fluid system is medium described by the Doubly Asymptotic Approximation (DAA) boundary element family of equations of either first or second order. Excitation may be that of a propagating shock wave through the fluid medium or of the explosion gas bubble pulsation. USA is written in FORTRAN 77 and is available by license for SGI IRIX 4.0.5 and 5.x as well as eight other UNIX platforms.

Karen Newcomb

Information Analyst