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A novel shear flow instability triggered by a chemical reaction in the absence of inertia

T. Burghelea·K. Wielage-Burchard·I. A. Frigaard·D. M. Martinez·J. J. Feng
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Abstract

We present an experimental investigation of a novel low Reynolds number shear flow instability triggered by a chemical reaction. An acid-base reaction taking place at the interface between a Newtonian fluid and Carbopol-940 solution leads to a strong viscosity stratification, which locally destabilizes the flow. Our experimental observations are made in the context of a miscible displacement flow, for which the flow instability promotes local mixing and subsequently improves the displacement efficiency. The experimental study is complemented by a simplified normal mode analysis to shed light on the origin of the instability

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T. Burghelea, K. Wielage-Burchard, I. A. Frigaard, D. M. Martinez, J. J. Feng. 2006-11-12. A novel shear flow instability triggered by a chemical reaction in the absence of inertia. https://arxiv.org/abs/physics/0611116

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