水冷式表冷器传热研究(6):机器露点表达式的建立

Heat transfer study on water-cooled surface air coolers(6): Establishment of mathematical expression of apparatus dew point temperature

建立了水冷式表冷器冷盘管表面平均热状态在干工况和湿工况下的数学表达式 ,通过理论和实验分析了各影响因素及影响程度。指出结构特性一定的表冷器 ,干工况下冷盘管表面平均热状态温度和进风干球温度、冷水初温成线性关系 ;湿工况下在空调常用范围内 ,冷盘管表面平均热状态焓值和进风焓值、冷水初温成线性关系 ,且两种工况下冷盘管表面平均热状态温度 (或焓值 )都随迎面风速增大而增大 ,随水流速增大而减小。

Establishes the mathematical expression of apparatus dew point of water-cooled surface air cooler under wet and dry cooling conditions. Analyses factors which affect apparatus dew point by theory and experience. Points out that to a given surface air cooler, the relation between apparatus dew point temperature and entering air dry bulb temperature or entering cooling water temperature is linear under dry cooling conditions, and the relation between apparatus dew point enthalpy and entering air enthalpy or entering cooling water temperature is linear under wet cooling conditions in common use. Apparatus dew point temperature or enthalpy increases when face velocity increases, and decreases when cooling water velocity increases under general conditions.