An Investigation on the Effects of Different Stratifications on Negatively Buoyant Jets

Abstract

Abstract. Negatively buoyant jets develop when fluids are released upwards into a lighter fluid or, vice versa, downwards into a heavier fluid. There are many engineering applications, such as the discharge, via submerged outfalls, of brine from desalination plants into the sea. Some concerns are raised about the potential negative environmental impacts of this discharge. The increase in salinity is the major cause for environmental impact, as it is very harmful to many marine species. The diffusers for brine discharge are typically inclined upwards, to increase the path before the brine reaches the sea bottom, as it tends to fall downwards driven by negative buoyancy. The negatively buoyant jet that develops conserves axisymmetry only when released vertically, so that it is not possible to use the well-known equations for axisymmetric jets. The main target of this paper is to investigate on a laboratory model the effects of different stratifications on the features of negatively buoyant jets. This has been done via a LIF (Light Induced Fluorescence) technique, testing various release angles on the horizontal and densimetric Froude numbers. Except for the initial stage, a different widening rate for the upper boundary and the lower boundary has been highlighted.

A Preliminary Study On The Inclination And Shape Of Jets Issuing From An Orifice In The Lateral Wall Of A Pipe

“…al., 2015[24],Ferrari et al., 2018a [25] and 2018b[26], [27], [28]), wave position(Ferrari et al, 2016 [29], Gallerano et al (2019)[30]), flow velocity(Querzoli, 1996 [31], Badas and Querzoli, 2011 [32], Simone et al, 2013 [33], Garau et al, 2018 [34], Badas et al (2019) [35]) and acceleration (Ferrari et al, 2007 [36], Ferrari and Rossi, 2008 [37], Ferrari et al, 2008 [38], Lardeau et al, 2008 [39], Rossi et al, 2009 [40]). Among the engineering fields of interest, the DIA techniques have been employed in the civil and industrial field (such as in the present paper), in the environmental field (Ferrari et al, 2016 [41], Badas et al, 2017 [42], or in Garau et al, 2017 [43], Di Bernardino et al (2017) [44], Ferrari et al, 2017 [45], Garau et al, 2018 [46], Badas et al, 2019 [47]) and biomedical fields (Badas et al, 2015 [48], Espa et al, 2012 [49], Querzoli et al (2019) [50]).…”

On The Effect Of The Shape Of Buildings And Chimneystacks On Ventilation And Pollutant Dispersion

“…Ferrari and Querzoli, 2010 [32],Ferrari et al, 2015 [33], Ferrari et al, 2018a[34] and 2018b[35]), wave position(Ferrari et al, 2016 [36]), velocity(Querzoli, 1996 [37], Badas and Querzoli, 2011[38], Simone et al, 2013[39], Garau et al, 2018[40]) and accelerations(Ferrari et al, 2007 [41],Ferrari and Rossi, 2008 [42],Ferrari et al, 2008 [43],Lardeau et al, 2008 [44],Rossi et al, 2009 [45]), in the civil and industrial (such as in the present paper or inGarau et al, 2017 [46]), environmental and biomedical fields (Badas et al, 2015[47], Espa et al, 2012[48]). …”