International Journal of Mathematical, Engineering and Management Sciences

ISSN: 2455-7749

Numerical Analysis of Liquid Mixing in a T-Micromixer with Taylor Dispersion Obstructions

T. Manoj Dundi
Mechanical Engineering Department, National Institute of Technology Warangal, Telangana State - 506004, India.

S. Chandrasekhar
Mechanical Engineering Department, National Institute of Technology Warangal, Telangana State - 506004, India.

Shasidar Rampalli
Mechanical Engineering Department, National Institute of Technology Warangal, Telangana State - 506004, India.

V. R. K. Raju
Mechanical Engineering Department, National Institute of Technology Warangal, Telangana State - 506004, India.

V. P. Chandramohan
Mechanical Engineering Department, National Institute of Technology Warangal, Telangana State - 506004, India.

DOI https://doi.org/10.33889/IJMEMS.2020.5.1.013

Received on January 03, 2019
  ;
Accepted on August 20, 2019

Abstract

Passive micromixers are of great importance in biomedical engineering (lab-on-chips) and chemical processing (microreactors) fields. Various hydrodynamic principles such as lamination, flow separation, and chaotic advection were employed previously to improve mixing in passive mixers. However, mixing enhancement due to velocity gradients in the flow, which is known as the Taylor dispersion effect, has been seldom studied. In the present study, thin rectangular slabs oriented in the flow direction are placed in the mixing channel of a T-micromixer. The thin rectangular slabs are referred to as Taylor Dispersion Obstructions (TDOs) as they are designed to create velocity gradients in the flow. The mixing performance of T-micromixer with and without TDOs is estimated in the Re range of 0 to 350. It is observed that there is no effect on mixing in the presence of TDOs in the low Re (0 < Re < 100), as the velocity gradients created in the flow are considerably small. The vortex formed in the flow for Re of 100 to 220 damped the gradients of velocity created in the flow (due to the presence of TDOs) which resulted in negligible improvement in the quality of mixing. However, considerable enhancement in mixing performance is obtained at high Re (250 to 350) with the presence of TDOs in the mixer. The increase in inertial effects at higher Recreated larger gradients of velocity near the walls of TDOs and mixing channel walls and thereby a significant enhancement in mixing performance is obtained due to Taylor dispersion.

Keywords- CFD, Micromixer, Mixing quality, Obstructions, Taylor dispersion, T-mixer.

Citation

Dundi, T. M., Chandrasekhar, S., Rampalli, S., Raju, V. R. K., & Chandramohan, V. P. (2020). Numerical Analysis of Liquid Mixing in a T-Micromixer with Taylor Dispersion Obstructions. International Journal of Mathematical, Engineering and Management Sciences, 5(1), 147-160. https://doi.org/10.33889/IJMEMS.2020.5.1.013.

Conflict of Interest

The authors confirm that there is no conflict of interest to declare for this publication.

Acknowledgements

The authors would like to express their sincere thanks to the referee for their valuable suggestions and Dr. M. Raja Vishwanathan for his support to improve the quality of research paper.

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