| Summary: | 碩士 === 中興大學 === 土木工程學系所 === 99 === The characteristics of bottom boundary layer flow induced by a solitary wave on 1:10 sloping bottom is experimentally investigated using the time-resolved particle image velocimetry (PIV). The velocity distribution of boundary layer can be classified into two parts for similarity analysis.Before the passing of wave crest of the solitary wave, a regression curve which consists of a hyperbolic tangent function was used to fit the velocity profiles. Corresponding characteristic values were calculated by this fitting curve. These characteristic values were used to conduct similarity analysis. Boundary layer, displacement layer momentum layer and energy layer were tried to be various length scales; and potential velocity (up) was selected as a velocity scale. Finally, four similarity curves could be obtained and all of the correlation coefficients are 0.970.After the passing of wave crest of the solitary wave, a regression curve combining both hyperbolic tangent function and cosine function was used to fit the velocity profiles. This study tried to select the subtraction of the potential velocity (up) minus the minimum velocity (um) as a velocity scale, and the half-velocity-defect (bm) as a length scale. Finally a similarity curve could be obtained for phases after the passing of wave crest and its correlation coefficients is 0.996.
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