Based on the second order random wave solutions of water wave equations in finite water depth, statistical distributions of the depth integrated local horizontal momentum components are derived by use of the charact...Based on the second order random wave solutions of water wave equations in finite water depth, statistical distributions of the depth integrated local horizontal momentum components are derived by use of the characteristic function expansion method. The parameters involved in the distributions can be all determined by the water depth and the wave number spectrum of ocean waves. As an illustrative example, a fully developed wind generated sea is considered and the parameters are calculated for typical wind speeds and water depths by means of the Donelan and Pierson spectrum. The effects of nonlinearity and water depth on the distributions are also investigated.展开更多
A new depth-integrated model deploying a non-hydrostatic pressure distribution is presented.With the pressure divided into hydrostatic and dynamic components,the horizontal momentum equations were obtained by integrat...A new depth-integrated model deploying a non-hydrostatic pressure distribution is presented.With the pressure divided into hydrostatic and dynamic components,the horizontal momentum equations were obtained by integrating the Navier-Stokes equations from the bottom to the free surface.The vertical momentum equation,in which the convective and viscosity terms were omitted,was approximated by the Keller-box scheme.The model has two steps.First,the dynamic pressure gradient terms were discretized semi-implicitly and the other terms were in explicit scheme.Second,the velocities expressed as the unknown dynamic pressure were substituted into the continuity equation,resulting in a five-diagonal symmetric matrix linear system that was solved by the conjugate gradient method.The model was validated with the propagation of a solitary wave and sinusoidal wave,indicating that it can predict free surface flows well.展开更多
A two-dimensional, depth-integrated model proposed by Lynett and Liu (2002) was checked carefully, and several misprints in the model were corrected after detailed examination on both the theory and the numerical prog...A two-dimensional, depth-integrated model proposed by Lynett and Liu (2002) was checked carefully, and several misprints in the model were corrected after detailed examination on both the theory and the numerical program. Several comparisons were made on wave profile, system energy and maximum wave amplitude. It is noted that the modified model can simulate the propagation of the internal solitary waves over variable bathymetry more reasonably to a certain degree, and the wave pro-files obtained based on the modified model can better fit the experiment data reported by Helfrich (1992) than those from original model.展开更多
文摘Based on the second order random wave solutions of water wave equations in finite water depth, statistical distributions of the depth integrated local horizontal momentum components are derived by use of the characteristic function expansion method. The parameters involved in the distributions can be all determined by the water depth and the wave number spectrum of ocean waves. As an illustrative example, a fully developed wind generated sea is considered and the parameters are calculated for typical wind speeds and water depths by means of the Donelan and Pierson spectrum. The effects of nonlinearity and water depth on the distributions are also investigated.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110142110064)the Ministry of Water Resources’ Science and Technology Promotion Plan Program of China (Grant No. TG1316)
文摘A new depth-integrated model deploying a non-hydrostatic pressure distribution is presented.With the pressure divided into hydrostatic and dynamic components,the horizontal momentum equations were obtained by integrating the Navier-Stokes equations from the bottom to the free surface.The vertical momentum equation,in which the convective and viscosity terms were omitted,was approximated by the Keller-box scheme.The model has two steps.First,the dynamic pressure gradient terms were discretized semi-implicitly and the other terms were in explicit scheme.Second,the velocities expressed as the unknown dynamic pressure were substituted into the continuity equation,resulting in a five-diagonal symmetric matrix linear system that was solved by the conjugate gradient method.The model was validated with the propagation of a solitary wave and sinusoidal wave,indicating that it can predict free surface flows well.
基金Sponsored by Knowledge Innovation Program of Chinese Academy of Sciences (CAS) and the project under the corporation of Institute of Oceanology, CAS and the China National Offshore Oil Corporation
文摘A two-dimensional, depth-integrated model proposed by Lynett and Liu (2002) was checked carefully, and several misprints in the model were corrected after detailed examination on both the theory and the numerical program. Several comparisons were made on wave profile, system energy and maximum wave amplitude. It is noted that the modified model can simulate the propagation of the internal solitary waves over variable bathymetry more reasonably to a certain degree, and the wave pro-files obtained based on the modified model can better fit the experiment data reported by Helfrich (1992) than those from original model.