Evaluation of methods to Estimate Hydrodynamic Force Coefficients of Underwater Vehicle based on CFD

Abstract

To know the motion performance of an underwater vehicle is important to achieve some missions. The motion equation is used to know the motion performance and the equation is described by hydrodynamic force coefficients and added mass components. Generally, these coefficients and components are derived by experiment such as forced oscillation test, but, especially for underwater vehicles, numerical method is desirable. Recently, numerical forced oscillation test has been applied to derive hydrodynamic force coefficients and the added mass components. But the validity of these coefficients and components are hard to evaluate. In this study, in regarding the result of the simultaneous solution of CFD and 6DOF motion simulation as correct solution, two kinds of numerical forced oscillation test methods are evaluated. As the result, certain method and parameter of the numerical forced oscillation test can express “correct solution” in high accuracy.