Hull shape optimization of autonomous underwater vehicles using a full turbulent continuous adjoint solver.

The present study aims at simultaneously optimizing the nose and tail of two distinct Autonomous Underwater Vehicles (AUVs) using a full turbulent continuous adjoint solver. The entire procedure is carried out utilizing two open-source software: Salome (CAD and mesh generator) and OpenFOAM v2206 (CFD solver and optimizer). Reynolds-Averaged Navier–Stokes (RANS) equations closed by the k- ω SST model are employed to simulate the turbulent flow around AUV hulls. Besides, adjointOptimisationFoam solver is used to perform the shape optimization. Two different unconstrained and constrained optimizations of AUV hulls are conducted at an angle of attack (α) equal to 0 °. In the unconstrained optimization, the drag force is chosen as an objective function to be minimized while a partial volume is considered as a geometric constraint in the constrained optimization. The predicted drag force is validated against experimental results from the literature, indicating a mere 0.58% discrepancy. In the unconstrained optimizations, the first and second AUV hulls reveal a 4.17% and 3.66% reduction in the drag force, respectively. In the constrained optimizations of the first and second AUV hulls, drag force is reduced by 3.25% and 2.63%, respectively. • Optimization of the noses and tails of two AUV hulls for drag minimization. • Optimization was done using a VEV continuous adjoint solver in OpenFOAM v2206. • Two optimization scenarios were considered: unconstrained and constrained. • In unconstrained optimization, the first AUV hull reduced drag by 4.17% and the second by 3.66%. • In constrained optimization, the first AUV hull reduced drag by 3.25% and the second by 2.63%. [ABSTRACT FROM AUTHOR]