The Structure Optimization of Flat Tube Fin in Direct-Cooled Condenser of Electric Power Plant

Abstract

To improve the efficiency of direct air-cooled condenser and optimize the physical structure of the flat tube fin, the 3D physics-mathematics models are set up and a CFD (Computational Fluid Dynamics) solver is employed to perform the numerical simulation. The flat wave-fin tube and the flat vertical-fin tube are calculated separately. In six wind conditions, the heat transfer coefficients, flow losses, heat dissipation, and the average surface temperature changes of the two kinds of fins are analyzed. The following conclusions are drawn: in vertical-fin flat tube, air flow space is larger and the turbulence intensity is lower. The average surface heat transfer coefficient of vertical-fin flat tube is smaller than the wave-fin flat tube. The flow loss of vertical-fin flat tube is less than the wave-fin flat tube by about 28.3 %. That will greatly reduce the power demand of the cooling fans and the energy loss of the whole power plant. The overall efficiency of the power plant will be improved. The heat dissipation amount of the vertical-fin flat tube is larger by about 8.82% than the wave-fin flat tube. The average surface temperature of the vertical-fin flat tube is higher than the wave- fin flat tube by 0.1 %. The numerical simulation results revealed that the flat vertical-fin tube is more efficient than the wave-fin flat tube in vapor condensation process.