Exhaust smoke dispersion for a generic frigate: Computational modeling and comparisons with experiments

The exhaust smoke dispersion for a generic frigate is investigated numerically through the numerical solution of the governing fluid flow, energy, species and turbulence equations. The main objective of the work is to obtain the effects of yaw angle, velocity ratio and buoyancy on the dispersion of the exhaust smoke. Turbulence is modeled using a two-equation (κk-ε) model. The flow visualization tests using 1/100 scale model of the frigate in the wind tunnel were also carried out to determine the exhaust plume path and to validate the computational results. The results show that down wash phenomena occurs for the yaw angles between ψ = 10° and 20°. The results with different exhaust gas temperatures show that the buoyancy effect increases with increasing exhaust gas temperature. However, its effect on the plume rise is less significant in comparison with its momentum. The agreement between the calculated results and experiments is found to be good.