环境影响下的直接空冷系统运行特性研究

环境变化会显著影响直接空冷机组的凝汽器压力,因此,研究直接空冷系统在环境影响下的运行特性,对保证直接空冷机组安全经济运行具有重要意义。通过理论分析,建立了空冷凝汽器温度和压力随汽轮机排汽热负荷、凝汽器迎风面风速以及进口空气温度变化的理论模型。以山西平朔煤矸石发电有限公司50MW机组直接空冷系统为例,通过数值计算,得到了环境气温、环境风速风向以及汽轮机排汽热负荷对凝汽器温度和压力的影响规律。结果表明:在凝汽器热负荷不变的情况下,环境气温越高,空冷凝汽器进口空气温度就越高,凝汽器压力就越高。环境风速越大,空冷器进口空气温度就越高,迎面风速就越小,从而凝汽器内冷凝温度和压力就越高。反之,凝汽器压力就越低。

Effects of Ambient Air on the Operational Characteristics of a Direct Air-Cooled Condenser System

The effects of the ambient air on the operational characteristics of a direct air-cooled condenser system are of great importance for the safe and economic operation of a direct air-cooled thermal power plant due to the significant influence of ambient changes on the condenser pressure of the air-cooled system.This paper presents a mathematical model for describing the variations of the condenser temperature and pressure with the exhaust steam heat load,frontal air speed and the inlet air temperature of an air-cooled condenser based on a theoretical analysis.The influences of the air temperature,wind speed and wind direction as well as the exhaust steam heat load on the condenser temperature and pressure are obtained by numerical calculation using the proposed mathematical model for a direct air-cooled condenser system in Shanxi Pingshuo Gangue-fired Electric Power Generation Company.The results show that for a condenser with a constant heat-load,the higher the ambient air temperature and wind speed,the higher the inlet air temperature of the direct air-cooled condenser and the lower of the inlet air flow rate,and correspondingly the higher the condenser pressure.On the other hand,the condenser pressure will fall when the ambient air temperature and wind speed decrease.