Abstract:

Direct dry cooling system adopts large-scale axial flow fan group to cool exhaust steam of turbine. So the noise of direct dry cooling system becomes one of the hazards of power plants. By using computational fluid dynamics software Fluent, the simulation of flow field and noise forecast of direct dry cooling cell and system were performed in this paper. The changes of flow field and noise of ACCs (air-cooled steam condensers) were simulated after increasing the noise reduction wall. The large eddy simulation was applied to analyze the flow field. Noise forecast was proceeded by means of the unsteady and implicit solver. The results show that the porous sound-absorbing materials decorated inside the wind wall have no effect on the flow field of ACCs. But they could effectively reduce the noise level of ACCs, especially reducing the low frequency noise.

Key words: direct dry cooling, axial flow fan, flow field simulation, noise forecast, noise reduction measures