Comparison of Two River Diffuser Models

Abstract

The effect of lateral boundaries on the mechanics of multiple shallow water jets in a coflowing current is studied. Two exact inviscid solutions of the momentum‐induced flow are examined: A model that accounts for the finite width of the receiving water is compared with a model that neglects lateral confinement. A parametric study reveals remarkably little difference in the key predictions of the velocity and contraction of the ultimate slipstream—especially with reference to a related recent study of boundary effects on multiple submerged jets. The conclusions are corroborated by detailed velocity measurements in a systematic set of experiments covering a wide range of induced flows.