The Behaviour of a Turbulent Buoyant Jet into Flowing Environment

Abstract

In this study the mean axial velocity at the centreline of a buoyant jet which is discharged vertically upwards from a source, into flowing environment inside a denser ambient fluid (water), in an open channel, is investigated. The presence of a buoyant jet is studied experimentally using a 2DParticle Image Velocimetry (PIV). For this reason individual experiments were conducted. Salt water is used as the ambient fluid and fresh water as the jet fluid. Experiments were made for flowing ambient fluid. For the flow visualization of the buoyant jet, the water, was dyed with either rhodamin (red color) or fluorescein (green color), aiming to the best appearance of the buoyant jet field. The velocity fields of the buoyant jet were determined analysing 200 pairs of photographs in each experiment. These fields were used to quantify the different behaviour of the buoyant jet into flowing environment. Results show that the presence of salt water can affect the flow dynamics with different way into flowing environment. The present findings are discussed and compared with other experimental data in similar conditions reported in the literature. These findings from experimental data analysis should be useful for the verification of numerical models.