THE POROUS EFFECT ON THE BOTTOM INSTABILITY UNDER PARTIALLY STANDING WAVES

摘要

In this paper, we extended Blondeaux, Liu, et al. [2] and Mei and Yu's theories to study the porous effect on instability of rippled bed under the partially standing surface waves. Comparisons are made with both Blondeaux and Mei & Yu's theoretical predictions and experimental data performed by many other authors. We found that based on the linear instability analysis and the parameter regimes we explored the percolation effect can change the threshold conditions by 10 ～ 20 percent and the seepage force is negligible up to O(∈). Furthermore, the steady streamings with or without porous effect show the considerable difference in intensities at the same locations and it might change the sediment transport rate especially the suspended load.