Sensitivity analysis and parameter optimization of energy consumption for underwater gliders

Most underwater gliders (UGs) operate on battery power, making energy a decisive factor for their duration and gliding range. Therefore, low power consumption technology is of great significance for enhancing the performance of UGs. In this paper, an accurate energy consumption model (ECM) and a gliding range model (GRM) of UGs are established. A field trial was conducted in the South China Sea to verify the accuracy of the ECM. To quantify the impact of different parameters on the ECM and GRM, the first-order and total sensitivity indexes of fourteen parameters are calculated through the Sobol sensitivity analysis method. The results indicate that gliding angle is the most influencing parameter on ECM, followed by velocity, diving depth, and drag coefficient K-D0. For the GRM, the order is diving depth, velocity, K-D0 and gliding angle. Based on a prototype UG, several simulations are performed to determine the optimal parameters leading to the maximum profile number and gliding range. The results demonstrate that with the same average diving depth of 1000 m, the optimal gliding range can increase by 11.97% compared with the gliding range in the actual sea trial. (C) 2019 Elsevier Ltd. All rights reserved.