Shape Optimization for A Conventional Underwater Glider to Decrease Average Periodic Resistance

As a type of autonomous underwater vehicle(AUV), underwater gliders(UG) are getting increasing attention in ocean exploration. To save energy and satisfy the mission requirements of a longer voyage, shape optimization for UGs has become a key technique and research focus. In this paper, a conventional UG, including its fuselage and hydrofoil, is optimized, which aims to decrease the average resistance in one motion cycle. To operate the optimization progress for the complex object, multiple free form deformation(FFD) volumes are established for geometric parameterization. High-fidelity simulation models are employed for objective function evaluation and gradients calculation. And sequential quadratic programming(SQP) method is adopted as an optimization algorithm.The optimization results show that there exists a UG with symmetrical and non-horizontal hydrofoils that has lower resistance.