本文对空气流过烧结微多孔介质内部对流换热进行了实验研究,分析了不同颗粒直径下对流换热努谢尔特数随流量的变化。结果表明;当颗粒直径为200~40μm时,实验得到的对流换热努谢尔特数与已有研究结果符合很好;当颗粒直径为20μm和10μm时,实验结果略小于已有研究结果,说明空气在微多孔介质中的对流换热需要考虑微尺度效应的影响。同时,根据实验结果给出了微多孔介质内对流换热努谢尔特数与雷诺数的经验关联式,并提出了考虑努森数的修正关联式。
The convection heat transfer between the solid particles and the fluid in microporous media were studied experimentally.The experimentally measured convection heat transfer Nusselt numbers for air in the microporous media with average diameters of 200μm to 40μm agree well with the published results.The experimental values for the Nusselt numbers for air in the microporous media with 10μm and 20μm average diameters are much less than the publish results.The results show that rarefaction effects occur in conv...