Difficulty in Determining Near-Surface Velocity Distributions Surrounding Wedged Drum Screens in Laboratory Environments

摘要

Wedged drum screens (WDS) are widely used to withdraw water from rivers and lakes with minimalrnimpacts on small fish and other aquatic life. These screens are generally designed to limit the peak flowrnvelocity at any point through the screen surface to 0.5 ft/s (15.2 cm/s). In order to produce uniformrnvelocity distributions over the entire screen surface both longitudinally and azimuthally, a variety ofrninternal flow modifiers are placed within cylindrical screens by different vendors. Computational FluidrnDynamics (CFD) codes are frequently used to design such internal flow-modifying devices. However,rnlaboratory data are often needed to verify such CFD predictions. Screen vendors and regulatoryrnagencies are particularly interested in knowing true velocities through screen slots.