Physics-Based Simulation of AUV Forced Diving by Self-Propulsion

Abstract

It is necessary to predict accurately the maneuverability of autonomous underwater vehicle (AUV) diving by self-propulsion to improve its safety and stability. A method was presented to predict the vehicle’s forces and flow details in real time during forced diving motion. A full appended model was built, the propeller’s rotating motion was simulated, and coupled with user defined function (UDF), the Reynolds-averaged Navier-Stokes (RANS) equations were solved. This method can improve the accuracy and computation efficiency of the dynamic mesh method by using multi-block mesh with the moving zone method. The numerical method was validated by comparison of the computational and experimental results of AUV’s velocity in AUV self-propulsion test. The numerical results of AUV forced diving by self-propulsion showed that, at the initial time, the AUV had a large acceleration which resulted in a large resistance. When the pitch changed, the vertical force oscillated. The wake of the propeller twisted and the thrust of the propeller varied. In steady diving, the thrust and resistance became steady.

Keywords

• autonomous underwater vehicle (auv)
• propeller
• dynamic mesh
• diving or rising motion
• physics-based simulation
• self-propulsion