One of the main causes of bedrock erosion is quicksand saltation on the bare bedrock. On the other hand, if bedrock is covered by gravel, bedrock erosion is restrained by decreased collision of quicksand on bedrock directly. And the topographic change by bedrock erosion cannot be calculated because we use
constant value of bedrock hydraulic roughness height (ksb). In this study, we tried to improve flume numerical calculation model (Nays 2d_bedrock) so that we can calculate the topographic change by using standard deviation of topography (σt). And we reproduce flumed channel experimental results using constructed model. In addition, we conducted numerical experiment imitating the “washing rock” which
is one of geographic features of bedrock erosion. The results suggest the following: (1) the numerical results correspond with past experimental results; (2) we can reproduce the “washing rock” by numerical experiment using standard deviation of topography (σt). |