Comparison of hydrodynamic characteristics of SUBOFF with cruciform and X-form rudder arrangement

Abstract

Objectives Underwater vehicles with an X-plane arrangement can be designed to handle plane control jams, and are characterized by their safety over vehicles with a cruciform arrangement. Because of the different arrangement and control mode of the X-plane arrangement, its hydrodynamic characteristics are different from those of a cruciform arrangement.Methods Numerical simulations of the cruciform arrangement are carried out on SUBOFF and validated first with the model test results and then in combination with the determined meshing method. The hydrodynamic characteristics of the X-plane arrangement are then studied and compared with those of a cruciform arrangement with the same rudder area. Finally, simulations of both the cruciform and X-plane arrangements with propellers modelled by body force are carried out.Results The results show that the horizontal and vertical stability coefficient of the X-plane arrangement is almost the same and declines compared with those of the cruciform arrangement respectively. The force characteristics of the X-plane arrangement are nonlinear with its angle, and the derivatives of the rudder decline by about 27%. The pump effect improves the stability coefficients and enhances the derivatives of the control surface by about 15%–18%.Conclusions The results of this study can provide guiding references for the design of underwater vehicles.

Keywords

• suboff
• control surface
• hydrodynamic characteristics
• statical instability coefficient
• numerical simulation