Foam-flow behavior in highly permeable porous media is still unclear. Two types of pregenerated foam using porous columns filled with fine sand and 1 mm glass beads were studied in different packs of glass beads with monodisperse bead size. Foam generated in fine sand had a sharp displacing front. However, the foam pregenerated using 1 mm glass beads had a transition zone front. We found that the transition foam-quality regime was independent of the porous medium grain size only when the bubbles are smaller than the pores. The apparent viscosity of foam was found to follow the Herschel–Bulkley model if the foam bubble sizes were smaller than the pore sizes. When the bubbles were of the same size as the pores, the foam behaved like a Newtonian fluid at low flow rates and, by increasing flow rates, exhibited shear-thinning fluid behavior. Furthermore, the apparent foam viscosity was found to increase with permeability.

中文翻译：

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高渗透性多孔介质中泡沫流动非牛顿行为的实验研究

在高渗透性多孔介质中的泡沫流动行为仍然不清楚。在装有单分散珠大小的不同玻璃珠包装中，研究了使用填充有细砂和1 mm玻璃珠的多孔柱制备的两种类型的预生成泡沫。在细沙中产生的泡沫具有锋利的移位前沿。然而，使用1mm玻璃珠预生成的泡沫具有过渡区前部。我们发现，仅当气泡小于孔时，过渡泡沫的质量状况才与多孔介质的晶粒尺寸无关。如果泡沫的气泡尺寸小于孔径，则发现泡沫的表观粘度遵循Herschel-Bulkley模型。当气泡的大小与孔大小相同时，泡沫在低流速下的行为类似于牛顿流体，并且通过增加流速表现出剪切稀化的流体行为。