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arXiv · 2412.01327

Compression-thinning behavior of bubble suspensions

Hu Sun·Qingfei Fu·Chiyu Xie·Bingqiang Ji·Lijun Yang
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Abstract

Rheology of bubble suspensions is critical for the prediction and control of bubbly flows in a wide range of industrial processes. It is well-known that the bubble suspension exhibits a shear-thinning behavior due to the bubble shape deformation under pure shear, but how the shear rheology response to dilatation remains unexplored. Here, we report a compression-thinning behavior that the bubble suspension exhibits a decreasing shear viscosity upon compressing. This peculiar rheological behavior is microscopically due to that a shrinking bubble surface effectively weakens the flow resistance of the surrounding liquid. We theoretically propose a constitutive equation for dilute bubble suspensions considering both shear and dilatation effects, and demonstrate that the contribution of dilatation effect on the shear viscosity can be significant at a changing pressure.

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Hu Sun, Qingfei Fu, Chiyu Xie, Bingqiang Ji, Lijun Yang. 2024-12-02. Compression-thinning behavior of bubble suspensions. https://arxiv.org/abs/2412.01327

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