The Effect of Bottom Friction on Shallow-Water Flow past an Isolated Obstacle.
The Effect of Bottom Friction on Shallow-Water Flow past an Isolated Obstacle.
复制标题
底部摩擦力对通过孤立障碍物的浅水流的影响。
DOI:
--
复制
发表时间:
1995
期刊:
影响因子:
--
通讯作者:
C. Schär
中科院分区:
文献类型:
--
作者:
V. Grubišić;Ronald B. Smith;C. Schär
Abstract The effect of bottom friction on fluid flow past an isolated obstacle is investigated in the shallow-water framework. The controlling parameter for this effect is the nondimensional bottom friction number, defined as a ratio of friction to inertia. With the bottom stress related to the horizontal wind via standard bulk aerodynamic formula, the friction number is proportional to the surface roughness, the horizontal scale of the obstacle, and the inverse of the upstream fluid depth. Thus, under otherwise identical conditions, the flow past larger obstacles will be more “viscous.” Bottom friction modifies the vorticity generation in several ways, but under normal conditions, the wake formation remains dominated by a pseudoinviscid process related to the presence of hydraulic jumps. However, friction strongly controls the velocity-deficit region of the wake and thus influences the stability of the steady-state wakes. Predictions of the linear stability analysis are compared with numerical simulation...