Assessment of Interceptor Effect on Hydrodynamic Coefficients of Longitudinal Equations of Motion of Planing Catamarans

Understanding the dynamics and behavior of high speed crafts, in calm water and waves is of vital importance. Determination of coefficients of equations of motion helps recognition of dynamics of high speed crafts and the factors affecting their instabilities which can be useful in controlling these instabilities. The main purposes of this research are determining the coefficients of longitudinal motions of planing catamarans using CFD and evaluating the Interceptor effect on hydrodynamic coefficients of a planing catamaran. Determination of hydrodynamic coefficients using experimental approaches is remarkably expensive, and requires precise laboratory equipment; therefore, using numerical method for hydrodynamic coefficients determination and development of a visual laboratory seems highly efficient. In this research the interceptor effect on hydrodynamic coefficients of a planing catamaran is evaluated. Results indicate most of the coefficients are frequency independence especially for high frequencies. Also, interceptor effect on hydrodynamic coefficients in different frequencies is negligible except for a few cases.