Design of terminator-shaped chamber-based micromixers with different obstructions: a CFD approach

Ranjitsinha R. Gidde; Meenakshi M. Pawar; Mohua Biswas

doi:10.1515/ijcre-2025-0072

Article

Design of terminator-shaped chamber-based micromixers with different obstructions: a CFD approach

Ranjitsinha R. Gidde , Meenakshi M. Pawar and Mohua Biswas

Published/Copyright: August 8, 2025

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From the journal International Journal of Chemical Reactor Engineering Volume 23 Issue 9

Abstract

This study investigates micromixers with terminator-shaped chambers and various obstructions using Computational Fluid Dynamics (CFD). The two types of obstructions, curved and angle-shaped, were used to create chaotic advection. For Reynolds values between 0.1 and 30, the effects of obstruction shape and constriction channel width on mixing performance were investigated. Plots of the ethanol mass fraction on the x–y plane at mid-height and on the y–z planes at different distances from the confluence point were used to investigate the mixing field and its characteristics. With the constriction channel width of 75 μm, the Micromixer with Curved–Shaped Obstructions (M-CSO) achieves a mixing efficiency of around 98 % at Re = 0.1 and Re = 30. With a constriction channel width of 75 μm, the Micromixer with Angle-Shaped Obstructions (M-ASO) achieves a mixing efficiency of around 99 % at Re = 0.1 and Re = 30. The findings demonstrate that the M-ASO exhibits superior mixing efficiency.

Keywords: split and recombine; terminator shape chamber; obstructions; convergent constriction channel

Corresponding author: Ranjitsinha R. Gidde, SVERI’s College of Engineering, Pandharpur, India, E-mail: rrgidde@coe.sveri.ac.in

Research ethics: Not applicable.
Informed consent: Not applicable.
Author contributions: Ranjitsinha R. Gidde conceptualized the study and led the writing. Meenakshi M. Pawar performed the data collection and analysis. Mohua Biswas contributed to the literature review and editing. All authors read and approved the final manuscript.
Use of Large Language Models, AI and Machine Learning Tools: The authors confirm that no large language models, AI, or machine learning tools were used in the preparation of this manuscript.
Conflict of interest: The studies described in this publication could not have been influenced by any known competing financial interests or personal relationships of the authors.
Research funding: No research funding is received for the research.
Data availability: Not applicable.

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Received: 2025-04-14

Accepted: 2025-07-17

Published Online: 2025-08-08

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Articles in the same Issue

https://doi.org/10.1515/ijcre-2025-0072

Keywords for this article

split and recombine; terminator shape chamber; obstructions; convergent constriction channel