振動流場における小口径円柱周辺の局所洗掘に関する3次元数値解析

We have developed a three-dimensional numerical model for temporal developments of flow and scour around a slender pile exposed to oscillatory flow. The flow model is based on the Navier-Stokes equations in moving generalized curvilinear coordinate systems and is coupled with a morphological model. The morphological model consists of the sediment mass-balance equation, the sediment transport models for bed load and suspended load, and the sand slide model. The calculations show that the present model reproduces the main features of the wave-induced scour processes. Detailed descriptions are given of the live-bed scour processes in conjunction with vortex flow and sediment transport. Investigations were also conducted on the effect of the sediment transport models on the numerical solutions