膜换湿过程热质耦合的分析与模拟  

ANALYSIS AND SIMULATION OF THE COUPLED MASS AND HEAT TRANSFER IN THE PROCESS OF MOISTURE EXCHANGE ACROSS A MEMBRANE

作　　者：胡腾[1] 闵敬春[1] 宋耀祖[1] 

机构地区：[1]清华大学航空航天学院工程力学系,北京100084

出　　处：《工程热物理学报》2010年第11期1913-1916,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.50576040)

摘　　要：从理论上分析了膜换湿过程中传质过程和传热过程之间的耦合关系,建立了相应的物理数学模型,发展了一种计算热质耦合的方法。分析结果表明传质过程对传热过程的影响主要体现在两方面:一是质量流携带的焓对传热过程的影响,二是吸附和脱附产生的吸附热对传热过程的影响。而传热过程对传质过程的影响主要体现在温度对膜湿阻的影响。采用数值模拟的方法对热质耦合过程进行了研究,结果表明:当热流与质量流方向相同时,热阻随湿度差的增大显著增大,而当热流与质量流方向相反时,热阻随湿度差的增大显著变小,而膜两侧湿度差对湿阻基本无影响。温度的升高会显著增大传质通量,同时降低湿阻,从而使得热流密度和热阻也受到显著的影响。The coupled mass and heat transfer in moisture exchange across a membrane was analyzed theoretically and the corresponding physical and mathematical model was established.A method was developed to calculate this coupling process.The result supports that the impacts of mass transfer on heat transfer show in two respects：one is that of the enthalpy carried by the flow and the other is that of the heat of adsorption,while the impact of heat transfer on mass transfer results from the impact of temperature on moisture resistance in membrane.The coupling process was simulated numerically and the results suggest that：in the case that the heat and mass transfer are in the same direction,the thermal resistance increases with increases the humidity difference,while in the case that the heat and mass transfer are in the opposite directions,the thermal resistance decreases with increasing the humidity difference.The effect of the humidity difference on the moisture resistance is negligible.A higher temperature will lead to a larger mass flow rate and a lower moisture resistance, which will influence the heat flux and thermal resistance.

关 键 词：热质耦合 湿阻 热阻 数值模拟 

分 类 号：TK123[动力工程及工程热物理—工程热物理]