Abstract We study in extensive detail the flow of dry and wet gas-liquid foams through a narrow two-dimensional channel comprising a complex constriction. The effects of constriction profile and size of aperture, foam flowrate, liquid holdup and liquid viscosity are experimentally investigated and a sophisticated image analysis procedure is developed to extract local fields of foam flow and deformation. Foam dynamics are scrutinised and interpreted in terms of local velocity distribution, elastic strain (texture tensor), plastic deformation (T1 events) and pressure drop. Important foam transformations occur in the vicinity of the constriction. For the first time, the relationship between pressure drop, flowrate and size of constriction aperture is investigated.

中文翻译：

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狭窄通道中泡沫流动、变形和压降的局部描述

摘要 我们广泛详细地研究了干湿气液泡沫流过包含复杂收缩的狭窄二维通道。实验研究了收缩轮廓和孔径大小、泡沫流速、液体滞留率和液体粘度的影响，并开发了复杂的图像分析程序来提取泡沫流动和变形的局部场。根据局部速度分布、弹性应变（纹理张量）、塑性变形（T1 事件）和压降来仔细检查和解释泡​​沫动力学。重要的泡沫转变发生在收缩区附近。首次研究了压降、流量与收缩孔尺寸之间的关系。