Experimental investigation on vibration isolation effectiveness of two sets of underwater vehicle dynamic systems

Power plant system is one of the major vibration sources in underwater vehicles. Isolation is by far the most effective approach to alleviate the vibration transmission from the power plant system to the shell. Underwater vehicle isolators are typically designed to be circular or distributed toroidal structures, and the shell is a thin-walled cylindrical structure. Such structures are extremely rare in other engineerings, and their isolation effectiveness has not been well explored. In this article, two sets of underwater vehicle dynamic isolation systems, i.e., heavy load rubber–metal composite isolators–shell (heavy load system) and light load metal–rubber isolators–shell (light load system), were tested. Our test results showed that the isolation effectiveness of the heavy load system was significant, whereas the light load system offered insignificant isolation because of the mismatch between the mechanical impedance of the shell and the isolators. To improve the vibration isolation effectiveness, some improvement measures were proposed based on the analysis results combined with the engineering practice in the last part.