A COMSOL SIMULATION OF MICROSPHERE-BASED PASSIVE MATERIAL FOR LOW TEMPERATURE DIVING SUITS

LT John A. Oldenkamp, USN

The United States Navy conducts diving operations in various places and climates all over the world. The neoprene wet suit protects the diver from cold water temperatures, extending the duration the diver can stay in the water. Neoprene is a soft material made of air-foamed rubber that uses small, flexible air pockets to thermally insulate a diver from the cold. However, as the diver descends, increased ambient pressure compresses the neoprene, decreasing its thickness and shrinking its air pockets. As a result, the suit鈥檚 insulation capability significantly degrades with depth, adversely affecting diver operations and persistence time at depth. One potential solution is the use of rigid glass microspheres as the thermally insulating material, which should be impervious to pressure changes associated with diving depth. This thesis develops a model using COMSOL Multiphysics software that can be used to theoretically verify previous work and provide the framework for computer simulations to predict the thermal resistivity of various materials as a function of microsphere composition, steric distribution, and volumetric fraction within the carrier polymer.