Free-Surface Flow Over Curved Surfaces
Abstract
Flood flows in excess of a reservoir's capacity must be passed downstream in a manner that does not endanger the dam or surrounding hydraulic structures. This is not a trivial task as the flow must fall a great distance to reach the riverbed. These high current velocities coupled with a free surface can easily lead to regions of low pressure in which cavitation may occur or the formation of standing waves and an uneven flow distribution. Poor flow distribution will yield circulation and high velocities at the base of the spillway (or outlet channel) known as the stilling basin, resulting in downstream scour, potentially undermining the structure, causing bank erosion and stilling basin damage. Numerical models of free-surface spillway flows must address high flow velocities and the nonhydrostatic pressure distribution over the curved spillway bed. Common shallow-water models invoke the hydrostatic assumption, and in the case of the St. Venant equations, also the mild-slope assumption and may not be adequate. This investigation develops the equations of a more general shallow-water formulation that includes bed curvature effects. The equations have lateral and longitudinal resolution and an assumed bed-normal velocity distribution. Finite element, Petrov-Galerkin, Nonhydrostatic, Shallow water.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1993
- Accession Number
- ADA269870
Entities
People
- Rutherford C. Berger Jr.