深度调峰工况下外圈配水湿式冷却塔模拟研究

Simulation study on water distribution in wet cooling tower under the deep peak load regulation condition

为了提升火电机组冷端系统在深度调峰状态下运行的经济性,本文以冷端辅助设备冷却塔为切入点,分别建立了凝汽器、循环水泵功耗模型和自然通风湿式冷却塔的数值模拟模型,提出了调峰工况下冷却塔外圈配水的运行方式并进行模拟研究。经研究发现,与全塔配水的运行方式相比,采用外圈配水的冷却塔,在循环水流量较低时,其出塔水温较低,冷却塔的通凤量较大;此外,出塔水温会随着环境温湿度和液滴粒径的减小而下降,外圈配水的出塔水温相较更低,对湿度的敏感性较小。最后,结合实际运行数据,对外圈配水运行方式进行经济性分析。结果表明,与全塔配水相比,在负荷低于44.2%额定负荷时,外圈配水冷却塔在单台低速泵运行的情况下其净收益功较高,最高可达0.125 MW。

In order 10 improve thermal power unit cold end system in the depth of peak shaving operation conomy of the state,respectively,the condenser and circulating water pump power consumption model and the numerical simulation of the natural wet cooling tower model is established.The study puts forward the operation mode of cooling tower under the condition of outer ring of water ditribution and simnulation studies with the breakthrough point which is the cold end of auxiliary equipment cooling tower.It is found that,compared with the common mode,the cooling tower with the outer ring water distribution has a lower outlet water temperature and a higher ventilation rate when the circulating watler flow is lower.In addition,the outlet water temperature decreascs with the decrease of ambient temperature and humidity and droplet size,and outer ring mode is lower.Finally,combined with the actual operation data,the economic analysis of the water distribution mode in the outer ring is carried out.The results show that,compared with the common mode,when the load is lower than 44.2%of the rated,the cooling tower in the outer ring water distribution has a higher net earning power,up to 0.125 MW,under the condition of a single low-speed pump.