Analyzing mixing quality in a T-shaped micromixer for different fluids properties through numerical simulation

Abstract

Microreaction engineering enables new strategies in process intensification. A precise analysis of local mass transfer and hydrodynamics in micromixers for different flow regimes are strongly needed for a complete understanding the processes occurring. One of the simplest in the manufacture, but at the same time, quite effective T-shaped micromixer was used for numerical investigation and analyzing the mixing quality and flow regimes as well as the influence of different fluids properties on this parameters. It was numerically revealed that the viscosities and the densities, as well as the initial temperatures and the rheology of mixing fluids have significant effects on the flow regimes and the mixing efficiency of two fluids. In this study viscosities and densities ratios of mixing fluids ranged from 1 to 2; the coefficient n in power-law model of non-Newtonian fluids ranged from 0.3 to 1; the initial temperatures difference of two fluids was varied up to 40ºC. Mixture components concentration as well as pressure and velocity fields distribution in the micromixer was obtained. The dependence of fluids mixing efficiency and the pressure drop, as well as a map of flow regimes and mixing modes on the Reynolds number and properties of miscible fluids was numerically established.

Investigation of mixing efficiency and pressure drop in T-shaped micromixers

“…It was shown in [14][15][16][17][18][19][20][21][22] that the value of the critical Reynolds number depends on the thermophysical properties of mixing fluids. Thus, it was found that as the fluids viscosities ratio increases the critical Reynolds number increases too, but such value doesn't depend on the fluids densities ratio.…”

“…Thus, it was found that as the fluids viscosities ratio increases the critical Reynolds number increases too, but such value doesn't depend on the fluids densities ratio. Also, the influence of the rheology of the mixing fluids on the shift of flow regimes in T-shaped micromixer [19,21,22] was pointed out.…”

Analysis of Hydraulic Mixing Efficiency in Widespread Models of Micromixers

“…The numeric technique used in this paper and the results of its testing are described in detail in the papers [23][24][25]. To solve the system of nonlinear differential Equations (1)-(5), we used the finite-volume method (FVM) [36,37].…”

“…During the conducted computations, the PD and the ME were calculated. To quantify the mixing efficiency, the parameter M = 1 − (σ/σ 0 ) 0.5 was used [20][21][22][23][24][25]41,42], where…”

Numerical investigation of flow regimes in T‐shaped micromixers: Benchmark between finite volume and spectral element methods

“…One of the most studied geometries is the T-shaped micromixer, in which the inlets perpendicularly join the mixing channel. Such geometry has been largely investigated numerically, highlighting the presence of both steady (stratified, vortex and engulfment, or steady asymmetric) regimes [13][14][15][16][17][18][19] and unsteady (asymmetric and symmetric time-periodic) regimes. [20][21][22] In particular the unsteady regimes were firstly discovered numerically, [14,20] and only subsequently they were observed experimentally.…”