环境风影响下直接空冷机组排汽压力的计算模型  

A Calculation Model of Exhaust Pressure of Direct Air-cooled Units Considering the Effect of Environmental Wind

作　　者：张学镭[1] 王金平[2] 陈海平[1] 

机构地区：[1]电站设备状态监测与控制教育部重点实验室(华北电力大学),河北省保定市071003 [2]中国国电集团公司,北京市西城区100034

出　　处：《中国电机工程学报》2012年第23期40-47,148,共8页Proceedings of the CSEE

基　　金：中央高校基本科研业务费专项资金资助(09MG34)~~

摘　　要：环境风对直接空冷机组的安全经济运行具有重要影响,预测环境风工况下直接空冷机组的排汽压力,是实施空冷岛优化运行的关键。针对某330MW直接空冷机组,建立了空冷凝汽器的数值分析模型,得到了各空冷单元的入口平均温度和空气流量,将排汽压力的计算尺度由空冷岛细化到空冷单元,建立了环境风影响下直接空冷机组排汽压力的计算模型。结果表明:位于环境风下游的空冷单元,其空气入口平均温度受环境风的影响较大,位于环境风上游的边缘空冷单元,其空气流量受环境风的影响较大;有风工况下直接空冷机组的排汽压力要比无风时高,正y方向环境风对排汽压力的影响要大于正x方向;环境风导致空冷机组排汽压力升高的主导因素是使空冷单元的空气流量减少。所建模型能预测出直接空冷机组受到环境风扰动后,达到稳定工况时的排汽压力。Environmental wind has obvious effect on the safe and economic operation of direct air-cooled unit. Key procedure of air-cooled condenser optimum operation is to forecast the exhaust pressure, especially under the operation condition of windiness. Take a certain 330MW direct air-cooled unit as an example, numerical model of air-cooled condenser was built, and the inlet mean temperature and air volume flow of every air-cooled heat exchanger unit were obtained. The scale of calculating exhaust pressure was refined from air-cooled condenser to heat exchanger unit, and the calculation model of exhaust pressure, which considering the effect of environmental wind, was built. The results show that the air inlet mean temperature of downstream heat exchanger units and the air volume flow of upstream edge heat exchanger units, are both seriously affected by environmental wind. The exhaust pressure under the condition of windiness is higher than that of windless condition, and the wind of positive y-direction has a greater influence on exhaust pressure than the wind of positive x-direction. The dominant factor of causing the rise in exhaust pressure under the condition of windiness is the decrease in the air volume flow of heat exchanger unit. The model built in the paper can forecast the exhaust pressure of direct air-cooled unit under the operation condition of windiness.

关 键 词：直接空冷 空冷凝汽器 环境风 排汽压力 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理] TK264[动力工程及工程热物理—热能工程]