表面式间接空冷散热器传热特性分析

Analysis of Heat Transfer Characteristics of Surface Indirect Air Cooled Radiators

以表面式间接空冷散热器为例,建立了间接空冷散热器冷却单元的一维传热数学模型。通过该模型,计算并分析了冷却水流量、温度及空气进口温度(环境温度)、流速等对空冷散热器传热性能的影响。计算结果显示,随着冷却水流量、温度和空气流速、温度的增大,散热器总传热系数逐渐增大;散热器总传热系数更接近于空气侧表面传热系数,其中空气流速对总传热系数的影响尤为明显;积灰对散热器传热性能的负面影响较大,积灰越厚,散热器总传热系数越小。另外,利用本文模型,得到了一定条件下间接空冷系统冷却水最佳流量,为间接空冷机组的运行了提供一定的理论依据。

Taking the air cooled radiator of surface indirect air cooling system as an example,a one-dimensional heat transfer mathematical model for cooling unit of indirect air cooled radiator were established. By this model,the influence of cooling water flow rate,temperature,air inlet temperature（ ambient temperature） and flow velocity on the heat transfer performance of air-cooled radiator were calculated and analyzed. Results show that,the overall heat transfer coefficient of the radiator increases with the increase of cooling water flow rate,temperature,air flow rate and temperature; the overall heat transfer coefficient of the radiator is closer to the convective heat transfer coefficient of the air side,especially the influence of the air velocity on the overall heat transfer coefficient; the negative influence of dust accumulation on the heat transfer performance of radiator is greater,and the thicker the dust accumulation is,the smaller the total heat transfer coefficient of the radiator is. In addition,the optimal cooling water flow rate of indirect air cooling system under certain conditions was obtained by using this model,which provides a theoretical basis for the operation of indirect air cooling unit.