Numerical Simulation of Direct Air-cooling Condenser with Rotary Flow Field and Spray Humidification

Based on Simple algorithm and k-e model,combined with heat and mass transfer theory for air-water two-phase flow,3D numerical simulations were carried out for a 600 MW direct air-cooling unit by using MRF model to treat the fan model,so as to analyze the influence of spray humidification on the condenser pressure.Results show that by applying MRF model to treat the fan model,the air spirals up in the unit,and both the air flow field and temperature distribution on heat exchanger is closer to actual conditions.The maximum pressure drop of condenser 8.97 kPa appears when the nozzles are symmetrically arranged 3.5 m away to trestle center of the fan,1.6 m above the outlet plane of fan shell,and the angle between spraying direction and positive direction of y axis is 210° in the xy plane,with a nozzle pressure of 0.8 MPa and nozzle diameter of 0.4 mm.