ABSTRACT
Jets are widely used in hydropower projects and environmental engineering, such as energy dissipation in plunge pool, sewage discharge in rivers and seas. With a Particle Image Velocimetry (PIV) system, the effects of jet’s geometry on the velocity decay of an oblique submerged-jet in a plunge pool were investigated. For the jets with different geometry, such as the normal jet and thin jet, the jet velocity distributions in the submerged region and wall-jet region are all self-similar, matching that of a free jet, though the flow pattern in the wall-jet region is in agreement with that of a submerged hydraulic jump. But the jet geometry has great effects on the velocity decay. With greater impact envelope, the velocity decay rate of the thin jet is greater than that of the normal jet, such as the https://www.w3.org/1998/Math/MathML"> u m u 0 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781351042666/80fff93d-0303-4aba-a754-97056619182a/content/eq553.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> decay rate of the thin jet is −0.275 in the submerged-jet region and −0.179 in the wall-jet region, yet the https://www.w3.org/1998/Math/MathML"> u m u 0 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781351042666/80fff93d-0303-4aba-a754-97056619182a/content/eq554.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> decay rate of the normal jet are only −0.0493 and −0.0387 respectively.
