The effect of chaotic advection on mixing degree and pressure drop of non-Newtonian fluids flow in curved micromixers

Abstract

Since the majority of fluids in engineering and biology applications are non-Newtonian, a numerical investigation was performed on the mixing of non-Newtonian fluids. Chaotic advection is one of the useful mechanisms to enhance the mixing performance which can be generated using curved micromixers. Therefore, mixing of non-Newtonian fluids in curved micromixers was studied in this study. The power-law fluids with power-law indices between 0.49 and 1 and Reynolds numbers between 0.1 and 300 were investigated. Open source CFD code of OpenFOAM was utilized to simulate mixing process in micromixers. The results showed that the mixing index decreases and dimensionless pressure drop increases by decreasing the power-law index. The chaotic advection and mixing index increase by increasing the Reynolds number for all values of power-law index. In addition, micromixers with sharp turns in their geometries yielded efficient mixing performance for low power-law indices and low Reynolds numbers.