侧风对喷淋蒸发预冷进风冷却塔换热性能的影响  

The influence of crosswind on the thermal performance of cooling tower with spray evaporative pre-cooling of the inlet air

作　　者：韩强[1] 冯雷[1] 刘严雪 毋飞翔 李鹏[1] 何锁盈 高明[2] HAN Qiang;FENG Lei;LIU Yanxue;WU Feixiang;LI Peng;HE Suoying;GAO Ming(Shandong Electric Power Engineering Consulting Institute Co.,Ltd.,Jinan 250013,China;Shandong Engineering Laboratory of High Efficiency Energy Saving and Energy Storage Technology and Equipment,School of Energy and Power Engineering,Shandong University,Jinan 250061,China)

机构地区：[1]山东电力工程咨询院有限公司,济南250013 [2]山东大学能源与动力工程学院高效节能及储能技术与装备山东省工程实验室,济南250061

出　　处：《流体机械》2022年第10期38-46,共9页Fluid Machinery

基　　金：山东省自然科学基金面上项目(ZR2022ME008);山东大学青年学者未来计划项目(2018WLJH73);能源清洁利用国家重点实验室(浙江大学)开放基金项目(ZJUCEU2020011)。

摘　　要：为了探明环境侧风对喷淋蒸发预冷进风空冷塔换热性能的影响规律,利用FLUENT 16.2软件建立了侧风下自然通风空冷塔的三维数值计算模型,采用数值模拟的方法,对比研究了有无侧风工况下空冷塔换热性能、预喷淋系统特性的变化规律。研究表明:侧风的存在使得空冷塔内均匀的空气动力场和温度场发生变化,主要表现为空冷塔迎风侧出现低速漩涡区,而背风侧通风效果较优,空气的流动影响塔内换热,导致迎风侧出现局部高温;加装喷淋蒸发预冷系统时,侧风使液滴掉落地面和流向散热器的趋势均有所减弱;针对半塔模型中仅引入3个喷嘴喷淋的情况,无风和侧风工况下液滴有效蒸发量分别是0.40,0.07 kg/s,对应的有效蒸发比分别为100%,17.5%,即无风工况下所有喷淋蒸发量均参与换热,而侧风工况下参与换热的喷淋蒸发量十分有限。因此,进行空冷塔喷淋预冷设计时,需考虑侧风影响,以利用少量水实现高温时段空冷塔换热性能提升的最大化。In order to study the influence of the crosswind on the thermal performance of cooling tower with spray evaporative precooling of inlet air,FLUENT 16.2 was used to establish a three-dimensional model of natural draft cooling tower under cross wind.Numerical simulation was employed to compare the variation rules of the thermal performance of the natural draft cooling tower and the characteristics of the spray pre-cooling system with and without crosswind.Studies show that the presence of cross wind changes the uniform aerodynamic field and temperature field in the dry cooling tower,which is mainly reflected in the low-speed vortex area on the windward side and better ventilation effect is on the leeward side of the cooling tower.The flow of air affects the heat transfer in the tower,causing local high temperatures on the windward side.When the spray evaporative precooling system is installed,the tendency of droplets falling to the ground and flowing to the radiator is weakened by cross wind;For the case of only three nozzles in the half-tower model,the effective evaporation of droplets is 0.40 kg/s and 0.07 kg/s respectively under the condition of no wind and cross wind,and the corresponding effective evaporation ratio is 100% and 17.5% respectively,that is to say,all the spray evaporation flux participates in the heat transfer under the condition of no wind,while the spray evaporation flux participating in the heat transfer under the condition of cross wind is very limited.Therefore,the influence of cross wind should be considered in the design of spray pre-cooling system of dry cooling tower to maximize the thermal performance of the dry cooling tower during high temperature periods by using a small amount of water.

关 键 词：自然通风空冷塔 侧风 喷淋蒸发 换热性能 数值模拟 

分 类 号：TH12[机械工程—机械设计及理论] TK124[动力工程及工程热物理—工程热物理]