고차 스펙트랄 기법을 이용한 수치 수조 시뮬레이션 연구

Abstract

In this study, the numerical wave tank was developed using a higher-order Spectral method and its characteristics were analyzed. The higher-order spectral method is known as a very efficient technique because it uses Fast Fourier transform(FFT) to calculate the boundary value problem without matrix operation. The cosine function was used as a pseudo-spectral basis to treat the wall boundary condition of the numerical wave tank. Also, the additional potential technique was introduced to reflect the boundary condition of the wavemaker. The results of numerical simulation applied with linear free surface boundary conditions were compared with the analytic solution of the wavemaker theory to validate the additional potential technique. A wave generation simulation applied the third-order nonlinear approximation method and the HOS method to the free surface boundary conditions, respectively, was performed and compared with the analytic solution. The characteristics of each technique were analyzed through the comparison results.