水膜热阻修正系数对填料饱和器性能的影响

Influence of Water Film Thermal Resistance Correction Factor on Performance of Packing Saturators

以单膜理论为基础,研究了饱和器内水与空气之间传热传质的过程,引入水膜热阻修正系数K的概念,建立了饱和器传热传质一维计算模型.通过数值模拟计算,分析了K对饱和器性能的影响,并确定了K设计值的取值范围.结果表明：饱和器出口水温、出口气温和出口空气含湿量受K设计值影响明显,K设计值越大,出口气温和出口空气含湿量越高,出口水温则越低;K设计值取得太小,水温和水膜温度相差较大,计算出的空气出口参数会偏小,反之,水膜温度几乎等于水温,计算出的空气出口参数会偏大,K设计值取15~100中的某一个值较为合理.

Based on single-film theory,the process of heat and mass transfer in packing saturator between water and air was studied,while the concept of water film thermal resistance correction factor（K） proposed,and a one-dimensional mathematical model built up.Through numerical calculation,influence of the correction factor on performance of the saturator was analyzed,after which the value range of K was determined.Results show that the K value obviously affects the outlet air temperature,outlet water temperature and outlet air humidity ratio;with the rise of K,both the outlet air temperature and air humidity ratio increase,and the outlet water temperature drops.If K is too small,the values of water temperature and water film temperature would differ a lot,and the calculated outlet air parameters would be smaller than actual values,whereas if K is too big,the result would be opposite.A reasonable K value should be some value between 15 and 100.