阻塞率

阻塞率(英文:constrictivity)[1],是一个用来描述在多孔介質输运过程无量纲參數。它由扩散颗粒的直径和孔径的比例而定其值。它的数值常常小于1。由于液体在孔壁附近的粘滞系数增加,因而液体在有孔介质内的输运阻力增大;这种效应对很小的孔,但有相同大小颗粒时,想要减小孔径的设计特别重要。

要区分努德森扩散(Knudson diffusion)和阻塞率的区别;前者着重颗粒和孔壁的相互作用多于科粒间的作用;而阻塞率着重液体和孔壁的相互作用。

实验证明阻塞率在较大范围内变化,仍能反应出其与阻力大小的关系。[2]

参考文献

  1. Renkin,EM(1954): Filtration,diffusion and molecular sieving through porous cellulose membrances,J. Gen. Physiologist,38:225-243.
  2. L.Holzer. et al. "The influence of constrictivity on the effect transport properties of porous layers in electrolysis and fuel cells" J.Mater. Sci.(2013)48:2934-2952.
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