摘要
对A型直接空冷单元流动换热特性进行了数值研究,分析了环境风速、风向、风温、平台高度等对空冷单元流动换热特性的影响。计算结果表明:环境侧风通过两方面影响空冷单元的性能,水平分速度严重影响通风量在散热器上的分配均匀性,垂直分速度严重影响风机的通风量。随着环境风速的增大,散热器的通风量减小,散热器温度升高,热回风率增加,风机压头有效利用系数降低;在同样环境风速下,Y向风是更不利的风向,应尽量避免;环境温度增加一方面提高了空冷单元的进风温度,另一方面减少了风机的通风量,使流动和换热恶化;在所研究的平台高度内,平台高度对空冷单元的流动和换热影响不大。研究结果可为空冷凝汽器的运行及优化设计提供参考。
The flow characteristics of A shape direct air - cooled condenser unit has been investigated numerically, And the five factors which are the crosswind velocity, platform height, environment temperature, windbreak height and the angle of incident flow are analyzed. The results indicate that the crosswind velocity and environment temperature increasing depress the mass flow rate through the radiator, and also decrease the mass flow rate of fan; and the effect of platform height is slight; the auction capacity of fan is improved with the windbreak downward continuation, and the effect is so slight when windbreak upward continuation; the mass flow rate of fan increase with the angle raise. The current results can serve as the reference for designing and operation of direct air-cooled condenser.
出处
《汽轮机技术》
北大核心
2011年第3期170-172,232,共4页
Turbine Technology
关键词
空冷单元
流场特性
换热特性
数值模拟
回流率
direct air cool
condenser unit
flow characteristics
numerical simulation
air recycle ratio
