1Department of Management Information System, Yung-Ta Institute of Technology and Commerce, Pingtung County 90941, Taiwan, R.O.C. E-mail: chency@mail.ytit.edu.tw,
2Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-sen University, Kaohsiung City 80424, Taiwan, R.O.C. E-mail: d9038809@student.nsysu.edu.tw,
3Center for Marine Technology, National Sun Yat-sen University, Kaohsiung City 80424, Taiwan, R.O.C. E-mail: ifan@mail.ncku.edu.tw, and
4Department of Logistics Management, Shu-Te University, 59 Hun Shan Rd.,Yen Chau, Kaohsiung County 82445, Taiwan, R.O.C.
#Corresponding author E-mail (Chen-Wu Chen): cwchen@mail.stu.edu.tw
ABSTRACT
This study analyzes the interfacial wave motion of a stratified two-layer fluid in a three-dimension domain. The proposed analytical solution considers the relationship between nonlinearity and frequency dispersion, but ignores viscous effects. The governing equations based on the Navier-Stokes equations are formed to simulate internal solitary wave (ISW) propagation over a variable seabed. In addition to numerical results, theoretical formulations are established to obtain analytical solutions. Numerical results indicate that at a given ratio of the height of a submarine ridge and the lower layer thickness, a depression-type ISW would generate a larger trailing oscillation than an elevation-type ISW. An elevation-type ISW is apparently evolved, while a depression-type ISW propagates on a trapezoidal shelf in a depth ratio, where the upper layer is thicker than the lower layer.
Keywords: internal solitary wave; Navier-Stokes equation; numerical model; variable bathymetry; wave fluctuation.