【摘要】 以某600 MW直接空冷机组为例,利用CFD软件对空冷岛采用地下进风布置方式的空气流场和温度场进行数值模拟;计算了空冷岛地上进风、地下进风(直、斜风道)以及空冷单元的通风量,分析了在主导风向下风速对直接空冷凝汽器换热效率及压力的影响。结果表明:在环境风的影响下,背风侧空冷单元的通风量大于迎风侧,但没有出现热风回流和倒灌;当环境风速大于4 m/s时,在同等条件下,地下进风的通风量较地上进风大,换热效率较地上进风高,凝汽器压力比地上进风低6~10 kPa。更多还原

【Abstract】 Numerical simulation of the air flow filed and temperature filed of the air-cooled island with underground ventilation was made with CFD software for a 600 MW direct air-cooling unit.The ventilation rate of air-cooling condenser and underground duct in different structure was calculated,the impact of wind speed on the heat transfer efficiency and pressure of direct air-cooled condenser under the prevailing wind direction was analyzed.The results showed that: under the influence of environment wind,the ventilation of condensers on the leeward side was greater than that on the windward side,but there was no hot air reflow and flow backward; When the ambient wind speed exceeded 4 m / s,under the same conditions,the total ventilation rate of air-cooled island with underground duct was greater than that on the ground,and the condenser average heat transfer efficiency was higher,the pressure of condenser was 6 ~ 10 kPa lower.更多还原