Theoretical Analysis and Optimal Design of Underwater Towed Body Dynamic Stability

This study presents the analysis of towed stability and the optimization design method for an underwater towed body, aiming to design a towing system with high stability, good hydrodynamic performance and a high degree of safety and reliability. By proposing analytical models for both the static and dynamic behavior of the towing system, the influence of the structural characteristics on the motion of the towed body were determined. The Computational Fluid Dynamics (CFD) method was employed to conduct hydrodynamic numerical simulations of the towed body, obtaining precise hydrodynamic coefficients. The optimization design of the towed body’s center of gravity and cable connecting point position was carried out. The simulation results systematically revealed the influence of towing speed and cable length on the dynamic behavior of the towed body. With the speed increasing from 4 kN to 20 kN the depth of the towed body reduces from 277.0 m to 90.6 m, the tension of the cable inreases from 11.5 kN to 171.85 kN. At a towing speed of 20 kN, the optimized towed body stay at an averaged pitch angle of 6.82° with very small roll angles. This research provides theoretical and numerical analyzing approach for the design of high-performance underwater towed bodies.