Near‐Field Model for a High‐Momentum Negatively Buoyant Line Source Within a Three‐Dimensional Hydrostatic Lake Model

Abstract

This work is motivated by a case study in which cooling water effluent is discharged from a line source diffuser onto the shallow southern shelf of a large lake. The effluent is discharged with high momentum to the north, and the plume influences the surrounding flow for hundreds of meters before becoming a passive tracer. We plan to use a three-dimensional hydrodynamic model to examine the impact of this effluent on water residence time within the southern shelf, but in order to accomplish this task, we require a method for incorporating the effluent-driven flow into the hydrodynamic model, which by default does not predict the correct rate of spreading of the plume or the correct rate of lateral entrainment of ambient water. In this paper we develop a method for incorporating the effects of high-momentum line source discharges into any three-dimensional or two-dimensional (depth-averaged) hydrodynamic model that employs a horizontal eddy viscosity and diffusivity. Our approach is to modify horizontal eddy viscosity and diffusivity to enforce the correct rate of lateral entrainment of the plume. We validate the new method using three test cases relevant to our case study: a neutrally buoyant jet, a cylindrical gravity current, and a negatively buoyant jet.

Experiment and Simulation of One Deep Sewage Discharge Type: Transport of Low‐Salinity Sediment‐Laden Flow Discharged

“…The centerline boundary of salinity, which is present in Figure 14 and Figure S1 in Supporting Information , shows a contracting immediately downstream of the nozzle for a short distance, and then, the boundary widens as it entrains ambient fluid, manifested as the first decrease and then increase of centerline radius of salinity r sa . This small segment of space is commonly called the acceleration zone while the latter is referred to as intermediate field as described by King and Cowen (2019). Unlike salinity, it looks like the temperature field shows more homogeneity of the water column, similar phenomena as Salmela et al.…”

“…A large amount of industrial and domestic wastewater are frequently discharged into lakes, oceans, or even reservoirs by various ways, which affects the local plankton (King & Cowen, 2019; Parnell, 2003; Zhao et al., 2013), fishery resources (Al‐Bahry et al., 2009; Porter & Janz, 2003), and ecological environment of lakes or oceans (Medema & Schijven, 2001; Terlizzi et al., 2002; Xue et al., 2013). Environmental water depth is an important factor affecting the dilution and diffusion capacity of sewage in polluted areas (Sha et al., 2017; Shen et al., 2019, 2021).…”

“…It introduced an interesting dual role of wind speed in evaporation from stratified and diluted plumes in hypersaline environments. King and Cowen (2019) developed a method for incorporating the effects of high-momentum line source discharges into any three-dimensional (3D) or two-dimensional (2D) model to modify horizontal eddy viscosity and diffusivity to enforce the correct rate of lateral entrainment of the plume. Zhao et al (2019) studied the mass transport for buoyant plume conducted in linearly stratified saltwater.…”

Discharge estimation of submarine springs in the Dead Sea based on velocity or density measurements in proximity to the water surface

“…Due to remarkable hydraulic gradients, SGD in the Dead Sea has a continuous origin of momentum at their orifice, and due to the large density differences between groundwater and the Dead Sea brine (up to 0.2 g cm− 3 ), they also have a continuous origin of buoyancy. Hence, the current formed under these conditions is a vertical, round, turbulent buoyant jet, a rather well-known phenomenon (Colbourne & Hay, 1990), which has recently been modified to correct for lateral entrainment by including horizontal eddy viscosity and diffusivity (King & Cowen, 2019) as well for waves (e.g., Ferrari, Grazia Badas, & Querzoli, 2018).…”

Propuesta de mejoramiento de capacidad hidráulica del emisor submarino de la PTAR La Chira mediante el uso del coeficiente de contracción de las válvulas de retención tipo Duckbill en el tramo difusor

“…Asimismo, un mal cálculo en el número de difusores y la distancia entre ellos reducen la dilución del efluente, tal es caso de emisores submarinos que tienen más cantidad de difusores, los cuales incrementan la capacidad de dilución a comparación de emisores que tienen un difusor sobre una gran área (King & Cowen, 2019). También, la colocación de válvulas es indispensable, ya que éstas realizan el trabajo de cierre de paso de agua de mar dentro del emisor.…”