| Summary: | 博士 === 臺灣大學 === 工程科學及海洋工程學研究所 === 98 === With fast development of the computer science, substantive efforts have been made in the computational fluid dynamics (CFD). Particularly a strong interest is focused on a new numerical method, namely, the meshless method. Since there is no mesh to distort, the meshless method can cope with large deformation in a Lagrangian framework. As a meshless method, the MPS (Moving Particle Semi-implicit) method has proven robust in a wide variety of naval architecture and ocean engineering including free surface flows. The MPS method is capable of dealing with problems in free surface, moving interface and wave propagation. Despite its applicability in many fields, the MPS method suffers unphysical numerical fluctuation of pressure with high frequencies. It leads the MPS method can not obtain accurate impact pressures. By implementing a new kernel function and the source term of Poisson pressure equation, a modified MPS method is proposed to suppress the pressure oscillation and obtained precise results in impact pressure prediction. The improved performance of the modified MPS method is validated by simulating the wave impact problems, such as the dam break problem, the droplet and wedge impact problem. Based on the previous research, some naval applications including bow flare impact and a floating body rolling in waves are introduced. The analyses show special advantage in simulating free surface flows.
|
|---|
