Design of micromixers using CFD modelling (original) (raw)

Computational Simulation of Enhancement of Mixing Efficiency in a Micromixer

Abstract—In this paper we studied the ways to enhance the mixing performance in a microchannel. The result's analysis shows a simpler pattern on the wall(s) of the microchannel can enforce rapid mixing of fluids and reduce the mixing length. The simple pattern on walls of the microchannel is easy to fabricate when compared to prevalent staggered herringbone mixer (SHM).The proposed mixer also creates the rotation of flow within the channel, which increases the interfacial area of the fluids. Thus reduces the mixing length of a microchannel. A twofold reduction in mixing length shown by the simulations can be of importance in designing micromixers of smaller size. The computational work also reproduces the experimental results of SHM as a part of validation. In addition to quantitatively reproducing the mixing efficiency plot found from experiments, the flow structures obtained in the simulations closely resemble the same obtained through experiments.

Computational fluid dynamics (CFD) simulation on mixing in Y-shaped micromixer

Computational Fluid Dynamics (CFD) is used to analyse the mixing process inY-shaped micromixer. This study used two different species which is ethanol/water and glycerol/water to see the differences of mixing quality between them based on their diffusion coefficient. The effect of the inlet velocity and mixing angle towards the mixing intensity in the Y-shaped micromixer were investigated via COMSOL Multiphysics software. Mixing intensity quantify the mixing performance is good or bad for every parameter simulated. The finding shows that the lower the inlet velocity, the higher the mixing intensity across the micromixer. The good mixing quality was at inlet velocity of 0.0001m/s while the ideal mixing angle was 90° degree. However, the mixing quality in term of diffusion coefficient, ethanol/water and glycerol/water shows insignificant differences.

Mixing Behavior and Pressure Drop Analysis of Micromixer with Different Geometric Conditions

International Journal for Research in Applied Science and Engineering Technology, 2021

A 3-D design of and analysis of fluid flow in the micromixer with different configurations is carried out in this dissertation. The main purpose of this research is to obtain minimum mixing length as rapid mixing is essential in many of the micro-fluidic systems used in biochemistry analysis, drug delivery, sequencing, or synthesis of nucleic acids. Also effect on various parameters such as mixing behavior, volume arrow, mixing length, maximum velocity, maximum pressure, pressure drop, and velocity distribution were analyzed by changing the mixing angle between inlets. Micromixers with square cross-section rectangular mixing chamber with various types of obstacle place in fluid flow paths such as rectangular obstacles, elliptical obstacle, and circular obstacle in split and recombination manner were designed for the analysis. The micromixer has 3 inlets and 1 outlet. Water and ethanol were used as working fluids. For computational fluid dynamics analysis, COMSOL Multiphysics 5.0 is ...

Numerical Study on Low Reynolds Mixing of T-shaped Micro-Mixers with Obstacles

Micromixers are one of the most crucial components of Lab-On-a-Chip devices with the intention of mixing and dispersion of reagents like small molecules and particles. The challenge facing micromixers is typically insufficient mixing efficiency in basic designs, which results in longer microchannels. Therefore, it is desirable to increase mixing efficiency, in order to decrease mixing length, which enables miniaturization of Lab-On-Chip devices. This study investigates two different designs of a passive T-shaped micromixer employing several rectangular obstacles and grooves to monitor mixing efficiency with geometry change, while keeping the Reynolds number under 2. The mixing performance of these geometries is studied by numerical study and it was implemented in COMSOL Multiphysics environment. It was clarified that T-shaped micromixer with obstacles and grooved micromixer improved mixing efficiency of the basic design by 37.2% and 43.8%, respectively. Also, it was shown that this ...