Numerical Simulation of Boundary Effects on the Groyne flow

• Main Authors: Yung-Hsing Wang, 王永興
• Other Authors: Chin-Wu Lan
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/74312712585047938849

碩士 === 國立中興大學 === 土木工程學系所 === 94 === Using the finite element method, this research simulates and solves the two-dimensional, steady, incompressible, and viscous turbulence flow. First, it changes the depth-averaged governing equation into the finite element model so as to proceed the operation of numerical simulation. In the process of the operation, arithmetic errors are made because of the side differences among elements and also because of the unfitness between the positions and distributions of nodes and the need of local accuracy. Therefore, the research uses the definition of the root-mean-square norm to estimate the errors, produced in the process of operation, of each element, and also to do the mesh relocation. In other words, to R-refinement the size and the location of each element without adding the number of elements and raising the degree of freedom of the shape function, so as to get the best mesh relocation. Centered on the groyne flow, this research uses boundary condition with free slip boundary and no slip boundary to do the operation separately, and further to discuss the results of uniform mesh and the automatic adaptive refinement. In order to raise the accuracy and the efficiency of the operation as well as the description of groyne flow field , the study uses two stages to push the mesh more densely .Then, compare the results of no slip boundary model according to the studies made before to get the identical tendency. The final step is to discuss the influences made by the Froude number, the Reynolds number, and the manning coefficient in the recirculation region of groyne.