Hydrodynamic performance optimization and adjustment prediction of a novel deep-sea towed body with adjustable hydrofoils

The towing stability of the towed body has an important impact on the data collection quality of the mounted sensors. In this paper, a novel deep-sea towed body control technology based on adjustable hydrofoils is proposed, and a hydrodynamic performance optimization and adjustment prediction strategy is established. Through computational fluid dynamics (CFD) simulation, the effectiveness of the adjustable hydrofoils in improving the towing stability of the towed body is verified, and the hydrodynamic mechanism of the adjustable hydrofoils is analyzed. The influence weight and influence law of the hydrofoil structural parameters on adjusted variables are determined by sensitivity analysis and main effect analysis, and the hydrodynamic performance optimization of the adjustable hydrofoil is completed based on the fast elitist Non-dominated Sorting Genetic Algorithm III (NSGA-III). A bidirectional Gaussian Process (GP) prediction model with respect to the angle of attack of hydrofoils and adjusted variables is established. The prediction model shows high prediction accuracy and strong generalizability, with the prediction error within 4%. The effectiveness of the novel towed body control technology is verified through sea trials. This paper provides reference and guidance for the development and engineering application of the towed body control technology.