Objectives To investigate the variation of the uniformity of the wake field on the propeller disk of an underwater vehicle with the tail fin axial position and the angle of run of the stern, and reveal the influence mechanism of the stern structure on the wake field.

Methods Numerical simulation analysis of underwater vehicle is carried out by computational fluid dynamics (CFD) method, and Gaussian process modeling analysis is performed for the index of wake field inhomogeneity to explore the response relationship between structure-field performance within the design range, to analyze the sensitivity of the stern structure to the wake field inhomogeneity, and to search for Suboff stern structure with excellent wake field homogeneity.

Results The results show that, with constant tail fin axial upwind area to ensure the efficiency of underwater vehicle operation performance and sailing, the tail fin axial position and the angle of run of the stern have a large impact on the propeller disk inhomogeneity; when the angle of run of the stern is \theta =10^\circ , the backward movement of the tail fin axial reduces the propeller disk inhomogeneity, and the wake objective function (WOF) decreases from 0.124 5 to 0.091 4; when the angle of run of the stern is \textθ=20^\circ , the backward movement of the tail fin axial causes the inhomogeneity of the propeller disk to first increase and then decrease, and the WOF increases from 0.104 9 to 0.114 5 and then decreases to 0.106 8; when the tail fin axial position is h= 3.810 0 meters, the increase of the angle of run of the stern makes the propeller disk inhomogeneity decrease, and the WOF decreases from 0.124 5 to 0.104 9; when the tail fin axial position is h= 4.114 8 meters, the increase of the angle of run of the stern makes the propeller disk inhomogeneity increase, and the WOF increases from 0.091 4 to 0.106 8; the adjustment of the Suboff stern structure using Gaussian process modeling analysis can effectively reduce the inhomogeneity of the wake field on the propeller disk.

Conclusions The study shows that for the Suboof model with fixed stern upwind area, the large tail fin axial position and small angle of run of the stern configuration can significantly enhance the propeller disk wake field uniformity, which provides guidance for the design of the stern structure of underwater vehicles.