Component layout optimization of thermal engine used by underwater gliders

The thermal-powered glider is a small, autonomous underwater vehicle which absorbs the energy of the ocean thermocline to propel the glider. The thermal engine is the key part of this glider, which affects the range and speed of the glider. The engine is composed of middle bellows, an accumulator, an external bladder, front bellows, and an electrical pump. In this paper, component layout of the thermal engine is analyzed and optimized. Result shows that the optimal position of the external bladder is at the tail while the optimal of the front bellows is at the nose. The optimal layout of the external bladder and the front bellows causes a 24% decrease in moving distance of the mechanical moving object. It is also found that the optimal positions of the accumulator and the middle bellows are close to the buoyant center. The overall moving distance of the mechanical moving object is reduced 43% by the optimal arrangement. Besides, a new thermal engine is developed by adding a gear pump to make the glider get across the areas short of temperature difference energy.