An innovative design of a compact shock isolation system to protect sensitive weapons from underwater shock & validated by shock testing for naval applications

Abstract

This paper presents an innovative solution to protect the sensitive weapons stored inside strategic submerged platforms from severe shock loads (170 g) due to underwater explosions. The shock loads mainly resulted from the underwater explosion of a nuclear warhead, mines, and bomb nearby platform. The underwater shock load has been analyzed, and a shock response spectrum (SRS) method has been developed to calculate peak responses during shock. The frequency of shock isolation has been selected from SRS to meet the requirement of shock isolation and sensitive weapon. Stiffness and damping characteristics were finalized to reduce the shock load of 179 g to an acceptable limit of 5 g for a sensitive weapon. The single-degree freedom system analytical model was formulated, and the ANSYS tool was used for modeling and simulation. The stiffness has been distributed over the weapon's length at multiple locations such that the weapon will oscillate in the translational mode under shock load from the elastic model. This paper explains the novel approach and technique for the design of a simple, unique, compact, reliable, electromagnetically compatible shock isolation system for underwater sensitive weapons. A parametric study was undertaken to compute the dimensions and configuration of shock isolators. Experimental tests were performed on the prototype to validate the design of the shock isolator. The maximum displacement of the isolator and maximum force transmitted to the sensitive weapon was found by shock testing. Finally, Transient dynamic analysis was performed to evaluate the actual motion of isolators during shock.