直接空冷机组喷雾增湿系统喷嘴布置位置数值研究

Numerical Study on Nozzle Layout of Spray Humidification System in the Direct Air-cooled Unit

为了提高直接空冷单元内喷雾增湿系统冷却效果,降低凝汽器出口空气温度,以计算流体力学理论为基础,建立了喷雾增湿系统数值计算模型,通过采用离散相模型对喷雾液滴轨迹进行跟踪,提出了"有效水份额"的概念,并应用到现有纵向双排喷嘴布置方案,分别在x/y/z 3个方向上对喷嘴位置进行了优化研究。结果发明,在x方向上喷嘴之间距离为2 m,y方向上喷嘴坐标y=0.5 m,z方向上喷嘴坐标为z=1 m时有效水份额最大,凝汽器出口空气温度最低,其结论是在喷嘴布置不能太密集且喷嘴的高度不能太低的条件下,喷嘴距离散热器越远,凝汽器出口空气温度越低。

In order to improve the cooling effect of spray humidification system in the direct air-cooling unit and reduce the outlet air temperature of the condenser,based on the computational fluid dynamics theory,a numerical computational model is established for the spray humidification system.Using discrete phase model,the droplet trajectory is tracked,and the concept of ＂effective water share＂ is proposed,the concept is applied to the existing longitudinal double row arrangement and the nozzle position optimization in x/y/z three directions is studied respectively.It is found that when the distance between two nozzles in x direction is 2 m and the nozzles located at y=0.5 m in y direction,z=1 m in z direction,the effective water share reaches a maximum,and the outlet air temperature of the condenser reaches a minimum.The conclusion is that if the distance between the nozzles and radiator becomes farther,the outlet air temperature will be lower.