Based on the Navier-Stokes equations and realizable k-ε turbulence model, a 3-D mathematical model for the round turbulent buoyant jet discharged vertically into cross flow was developed. The temperature distribution is well in agreement with the experimental data in the vicinity of the jet. Numerical results indicated that the jet entrains the ambient fluid during its rising stage and deflects from initially vertical direction towards horizontal direction. They also suggested that the undersea discharge guarantees maximum dilution and minimal effect on the marine environment and can be efficiently used in offshore water areas.
The exhaust heat discharge into natural bodies of water is one of the environmental problems that have received considerable attention in recent years. The typical industrial background for turbulent flow and heat transport problems concerned in this paper is associated with coastal engineering systems, such as thermal or nuclear power stations. The system pumps the coastal water into its cooling water circulation, and discharges the heated water produced by engineering operations into natural bodies. The resultant thermal discharge may have a significant impact on the marine environment. Therefore, it is very important to understand the behaviors of flow pattern and heat transport processes for prevention of damage to the ocean environment caused by thermal pollution into coastal water areas. There are considerable researches on the mechanics of buoyant jets related to the turbulent heat transport processes in the past three decades. Previous studies of buoyant jets were based mainly on mathematical models and a few field samples made in real time, which includes notably the works by Stolzenbach and Harleman (1973), McGuirk and Rodi (1979), Yu et al. (1987), Sobey et al. (1988), Demuren (1993), Bemporad et al. (1994), Johnston et al. (1994) and Jiang et al. (2002).