自然通风湿式冷却塔空气动力场数值分析

对电厂自然通风逆流式双曲线冷却塔内的空气动力场进行了数值分析,并利用PHOENICS计算平台进行了数值模拟。分析结果认为:冷却塔无风运行时,塔内形成负压,压力沿塔高逐渐升高;塔内流场呈轴对称分布时,塔内周向分布均匀,中心流速最大。由于冷却塔的冷却能力受环境的影响很大,还对淋水密度、环境温度、阻力变化等各种变工况进行了计算与比较,发现入塔水温与淋水密度对塔内流场的影响基本相当。

NUMERICAL ANALYSIS OF AERODYNAMIC FIELD IN WET TYPE NATURALDRAFT COOLING TOWER

The numerical analysis of aerodynamic field in wet type natural-draft reverse-flow hyperbolic cooling tower has been carried out,and its numerical simulation being performed by using PHOENICS computing platform.It is believed from results of analysis that: a negative pressure is created in the lower under calm and stable operation state of the cooling tower,the pressure to be gradually enhanced along with increasing the tower height;the flow field in the tower to be axisymmetrically distributed,and the circumferential distribution to be uniform,the central flow velocity to be max.Because the cooling power of the tower is greatly affected by the environment,various off-design conditions,including water-spraying density,ambient temperature,and resistance variation etc.,have been calculated and compared.It was found that the influence of inlet water temperature of the tower to be basically equivalent to that of the water-spraying density upon the flow field in the tower.