Wave-mud Interaction with Wave Attenuation Mechanisms

• Main Authors: Lung-HsiangChang, 張隆翔
• Other Authors: Huang-Hui Huang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/50700794902637733011

碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 98 === The paper focus on the attenuation of surface wave caused by the interactions between mud and wave.The damping of the surface wave can be considerable after only a few wavelengths.When surface wave propagates over the mud beds, the dynamic respone of fluild mud is main mechanism for damping. Several parameters have influence on energy dissipation, including wave height, wave period, water depth and rheology properties of mud. These factors will be experimentally investigated and damping mechanism is presented in this paper. The mixture Kaolin with water was selected as fluid mud in the experiment and the rheology property was test by rheometer. Different levels of mud density, wave heights and wave periods are tested. Capacitance-type wave gages were used to measure surface wave heights attenuation along the trench, and two CCD cameras were used to monitor interface elevation at fixed position. The electromagnetic current meter (EMC) is applied to measure horizontal and vertical velocity distribution in the vertical column. The results reveal that energy dissipation depends not only on wave length and rheology of mud, but also highly depends on wave steepness. Base on non-dimensional parameter and experimental data, we modify the damping theory by adding conceptual energy. The new formula agree fairly with experimental data. Furthermore, the induced boundary layer thickness and phase difference in the fluid mud was presented.