The development of the quasi three dimensional numerical model of coastal hydrodynamics

• Main Authors: Wu, Zenyo, 吳仁友
• Other Authors: Huang Liang-Hsiung
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/42587518089506984016

碩士 === 國立臺灣大學 === 土木工程學系研究所 === 85 === Using Dr. W. S. Chu''s depth-averaged two-dimensional "Harbor Hydrodynamic Mo del", and referring to vertical/horizontal splittingalgorithm, VHS in short,in Lardner and Cekirge(1988), the presentstudy develops a quasi three dimensiona l hydrodynamic model by splitting three dimensional computation of coastal hyd rodynamics into horizontal two dimensional and vertical one dimensional comput ations. Space discretization method given by Leendertse and Liu(1973,1975) and explicit leap frog scheme are applied to horizontaltwo dimensional computatio n, while Lardner and Cekirgr*s(1988) procedure and Crank-Nicholson scheme are used to obtain vertical velocity profile after horizontal two dimensional mode l were proceeded. This quasi three dimensional model saves a lot of CPU time a nd storage space compared to real three dimensional, but still gives good qual ity vertical information by merely taking similar computationcost as the horiz ontal two dimensional model. Besides, this study improves the constrains of o pen boundary conditions in HHM, hence more freedom are allowed at the open bou ndary.The geometry of the open boundary is used to limited to be either perpen dicular or parallel to the grid, it is now improved to irregular coordinated. And in order to capture the real phenomena of the appearing of stationary curr ent near the west coast of Taiwan, the original constraint that allows only ti dal input and zero velocity gradient at open boundary condition in HHM is rele ased and both tide and current can be given at the open boundary.