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This paper presents the numerical simulation of single, circular, turbulent, thermal jets discharged into an ambient fluid body with a uniform cross flow. The study utilizes a 3D hydrodynamic model to predict the dynamics of the evolving jets, with the model simulations calibrated against benchmark laboratory experimental datasets. Within the numerical-experimental model comparisons, the mean centreline temperature and velocity fields of the evolving jets are investigated in order to understand and predict the jet diffusion characteristics within the flowing ambient fluid body. Direct comparison between the numerical model predictions and laboratory datasets reveals that, with appropriate parameterization of the mixing processes and the selection of an appropriate numerical grid resolution, the large-scale hydrodynamic model can simulate both the near- and far-field thermal jet behaviour with good overall agreement, thus revealing a valid modelling tool used by environmental regulators for assessing the conformity of water quality of marine wastewater discharges. [ABSTRACT FROM AUTHOR]

The Coastal Engineering Laboratory (LIC) of the DICATECh of the Polytechnic University of Bari (Italy) maintains a place-based research program in the Mar Grande and Mar Piccolo of Taranto (a coastal system in southern Italy), providing records of hydrodynamic and water-quality measurements. This site is one of the most complex marine ecosystem models in terms of ecological, social, and economic activities. It is considered highly vulnerable for the presence of the naval base, of the biggest refinery of Europe and of the oil refinery. Two fixed stations have been installed, one in the Mar Grande (MG station) and another in Mar Piccolo (MP station). In the MG station constituents include wind speed and direction, air temperature and humidity, barometric pressure, net solar radiation, water salinity, water temperature, water pressure, dissolved oxygen, fluorescence, turbidity, CDOM, crude oil and refined fuels, sea currents and waves. In the MP station constituents include water temperature, sea currents and waves. We provide a summary of how these data have been collected by the research group and how they can be used to deepen understanding of the hydrodynamic structures and characteristics of the basin. These data are available at https://doi.org/10.5281/zenodo.4044121 (Mossa et al., 2020). [ABSTRACT FROM AUTHOR]

This paper presents the application of a weakly compressible smoothed particle hydrodynamics model to study plane jets propagating into a still ambient and into a flow field of regular waves. The present study includes a comparative investigation of the main fluid mechanics characteristics in cases of jet discharged either in still water or transversally to regular wave trains characterized by different periods. Concerning jets in a wave environment, the present study shows the existence of the following three different regions of the jet-wave field starting from the nozzle in the intermediate water: the nearest region to the nozzle where the jet motion dominates the wave motion; the intermediate region, where the horizontal velocity component of wave motion dominates the jet centreline velocity decay; and the nearest region to the free surface where the wave period dominates the jet motion. The present study shows the differences found numerically between each flow region. [ABSTRACT FROM AUTHOR]

The present paper, places emphasis on the vorticity induced by wave breaking, which greatly contributes to sediments pick up and suspension as well as to air–water exchange at the wave interface, thus deserving a thorough study. A weakly-compressible smoothed particle (WCSPH) model, coupled with a two-equation model for turbulent stresses, has been employed for this scope. A careful calibration of the SPH's numerical parameters has been first performed, based on experiments carried out in a sloped wave channel, specifically using wave elevation and velocity data. Once proved the reliable performance of the model, the characteristics of vorticity induced just prior and post breaking for both the cases of a spilling and a plunging wave have been numerically studied. The main and detailed results indicate that for both the types of breakers there is a cause-effect relation observed between the stream wise flow deceleration and the vorticity generation. [ABSTRACT FROM AUTHOR]