Optimal design of combined propulsion Underwater Glider for operation of the East Sea of South Korea

An underwater glider is an autonomous underwater vehicle that is propelled by changes in volume. Due to this propulsion method, it is possible to make observations with these devices continuously for 30–60？days. Of the gliders’ physical properties, the volume change has the greatest influence on the cruising speed. The speed can be increased by increasing the volume change, but this also increases the energy consumption. Therefore, the change in buoyancy is very important for the operation of underwater gliders. Hence, it is necessary to optimize the change in buoyancy. In this study, we describe a technique for optimizing the design of underwater gliders intended to operate in the East Sea of Korea using a combined buoyancy engine and thruster propulsion system. First, we carried out a simulation study to optimize the volume change of the buoyancy engine based on the average flow velocity distribution, water temperature, and vertical salinity distribution in the East Sea. Then, we used our simulations to predict the optimal change in volume of the underwater glider. Finally, we discuss the advantages of operating with thrusters in special environments under specific water temperature, salinity distribution, and ocean current conditions