Document Type : Research Paper


1 Iran university of science and technology Mechanical Engineering Department

2 Mechanical engineering department, Iran university if science and technology


Micromixer is a significant component of microfluidics particularly in lab-on-chip applications so that there has been a growing need for design and fabrication of micromixers with a shorter length and higher efficiency. Despite most of the passive micromixers that suffer from long mixing path and complicated geometry to increase the efficiency, our novel design suggests a highly efficient micromixer while taking advantage of having a short length. The novelty of our work stems from utilizing all three mixing techniques of injection, recombination, and zigzag mixing resulting in benefits such as multi-flow lamination and flow resistance reduction in microscale. Moreover, the contraction and expansion of the microchannel width improve mixing. The present work deals with the parametric study, numerical simulation, as well as experimental tests and characterization of small planar passive micromixer. The high mixing efficiency yield of 98.02 was obtained with the length of only 1857.8 microns which shows good agreement in comparison with numerical simulation.

Graphical Abstract

Design and fabrication of an effective micromixer through passive method


Main Subjects

[1]      A. Cosentino, H. Madadi, P. Vergara, R. Vecchione, F. Causa, and P. A. Netti, “An efficient planar accordion-shaped micromixer: From biochemical mixing to biological application,” Sci. Rep., vol. 5, no. November, pp. 1–10, (2015). 


[2]      S. Hossain, M. A. Ansari, and K. Y. Kim, “Evaluation of the mixing performance of three passive micromixers,” Chem. Eng. J., vol. 150, no. 2–3, pp. 492–501, (2009). 


[3]      M. A. Ansari, K. Y. Kim, K. Anwar, and S. M. Kim, “A novel passive micromixer based on unbalanced splits and collisions of fluid streams,” Micromechanics Microengineering, vol. 20, no. 5, (2010). 


[4]      X. Chen and T. Li, “A novel design for passive misscromixers based on topology optimization method,” Biomed. Microdevices, vol. 18, no. 4, pp. 1–15, (2016). 


[5]      X. Chen, T. Li, and Z. Hu, “A novel research on serpentine microchannels of passive micromixers,” Microsyst. Technol., vol. 23, no. 7, pp. 2649–2656, (2016). 


[6]      X. Chen and T. Li, “A novel passive micromixer designed by applying an optimization algorithm to the zigzag microchannel,” Chem. Eng. J., vol. 313, pp.1406–1414,(2016). 


[7]      L. Capretto, W Cheng, M. Hill and X. Zhang, “Micromixing Within Microfluidic Devices,” Microfluidic., vol. 35, no. 1, pp. 27–68, (2011). 


[8]      S. Gambhire, N. Patel, G. Gambhire, and S. Kale, “A Review on Different Micromixers and its Micromixing within Microchannel,” International Journal of Current Engineering and Technology, vol.4,no.4,(2016). 


[9]      Mengeaud V, Josserand J, Girault H, “Mixing processes in a zigzag microchannel: finite element simulations and optical study,” Anal Chem, 74(16):4279–4286, (2002). 


[10]    Hong C, Choi J, Ahn C, “A novel in-plane passive microfluidic mixer with modified Tesla structures,” Lab Chip, 4(2):109–113,(2004). 


[11]    Sudarsan A, Ugaz V, “Fluid mixing in planar spiral microchannels,” Lab Chip,6(1):74–82,(2006). 


[12]    Hardt S, Pennemann H, Sch€onfeld F, “Theoretical and experimental characterization of a low-Reynolds number split-and-recombine mixer,” Microfluid Nanofluid, 2(3):237–248, (2006). 


[13]    Yang J, Huang K, Tung K, Hu I, “A chaotic micromixer modulated by constructive vortex agitation,” J Micromech Microeng, 17:2084, (2007). 


[14]    Bhagat A, Peterson E, Papautsky I, “A passive planar micromixer with obstructions for mixing at low Reynolds numbers,” J Micromech Microeng,17:1017,(2007). 


[15]    Park J, Kim D, Kang T, Kwon T, “Improved serpentine laminating micromixer with enhanced local advection,” Microfluid Nanofluid, 4(6):513–523,(2008). 


[16]    Long M, Sprague M, Grimes A, Rich B, Khine M, “A simple three-dimensional vortex micromixer,” Appl Phys Lett, 94:133501, (2009). 


[17]    X V.E. Papadopoulos, I.N. Kefala, G. Kaprou, G. Kokkoris, D. Moschou, G. Papadakis, E. Gizeli and A. Tserepi, “A passive micromixer for enzymatic digestion of DNA,” Microelectron. Eng., vol. 124, pp. 42–46, (2014). 


[18]    S. Hossain and K. Kim, “Mixing Analysis in a Three-Dimensional Serpentine Split-and-Recombine Micromixer,” Chem. Eng. Res. Des., (2014). 


[19]    P. Chen, C. Pan, and Y. Kuo, “Process Intensi fication Performance characterization of passive micromixer with dual opposing strips on microchannel walls,” Chem. Eng. Process. Process Intensif., vol. 93, pp. 27–33,(2015). 


[20]    X. Chen, T. Li, H. Zeng, Z. Hu, and B. Fu, “Numerical and experimental investigation on micromixers with serpentine microchannels,” HEAT MASS Transf., vol. 98, pp. 131–140, (2016). 


[21]    T. Xie and C. Xu, “Numerical and experimental investigations of chaotic mixing behavior in an oscillating feedback micromixer,” Chem. Eng. Sci., vol. 171, pp. 303–317,(2017). 


[22]    W. Raza, S. Hossain, and K. Kim, “Effective mixing in a short serpentine split-and-recombination micromixer,” Sensors and Actuators B:Chemical,(2017). 


[23]    S. Hossain, I. Lee, S. Min, and K. Kim, “A micromixer with two-layer serpentine crossing channels having excellent mixing performance at low Reynolds numbers,” Chem. Eng. J., vol. 327, pp. 268–277, (2017). 


[24]    K. Chen, H. Lu, M. Sun, L. Zhu, and Y. Cui, “Design Mixing enhancement of a novel C-SAR microfluidic mixer,” Chem. Eng. Res. Des., vol. 132, pp. 338–345, (2018). 


[25]    P. Hermann, J. Timmermannb, M. Hoffmannb, M. Schlüterb, C. Hofmannc, P. Löbc and D. Ziegenbalg, “Optimization of a split and recombine micromixer by improved exploitation of secondary flows,” Chemical Engineering Journal, vol. 334, no. November 2017,pp.1996–2003,(2018). 


[26]    P. Vatankhah and A. Shamloo, “Parametric study on mixing process in an in-plane spiral micromixer utilizing chaotic advection,” Anal. Chim. Acta, vol. 1022, pp. 96–105, (2018). 


[27]    M. Nabil, S. H. El-emam, M. H. Mansour, and M. A. Shouman, “Development of an efficient uni flow comb micromixer for biodiesel production at low Reynolds number,” Chemical Engineering and Pro-cessing - Process Intensification, vol. 128, pp. 162–172,(2018). 


[28]    A. Husain, F. A. Khan, N. Huda, and M. A. Ansari, “ Mixing performance of split-and-recombine micromixer with offset inlets,” CMicrosyst. Technol.,(2017). 


[29]    R. R. Gidde, P. M. Pawar, B. P. Ronge, N. D. Misal, R. B. Kapurkar, and A. K. Parkhe, “Evaluation of the mixing performance in a planar passive micromixer with circular and square mixing chambers,” Microsyst. Technol.,(2017). 


[30]    X. Chen and Z. Zhao, “Numerical investigation on layout optimization of obstacles in a three-dimensional passive micromixer,” Anal. Chim. Acta,(2017). 


[31]    P. Mehrdel, S. Karimi, and J. Farr, “Novel Variable Radius Spiral – Shaped Micromixer : From Numerical Analysis to Experimental Validation,” Micromachines., vol. 9, no. 552, (2018). 


[32]    J. Zhang and X. Luo, “Mixing Performance of a 3D Micro T-Mixer with Swirl-Inducing Inlets and Rectangular Constriction,” Micro-machines., vol. 9, no. 199,(2018). 


[33]    Z. Wu and X. Chen, “A novel design for 3D passive micromixer based on Cantor fractal structure,” Microsyst. Technol.,vol.7,(2018). 


[34]    X. He, T. Xia, L. Gao, Z. Deng, and B. B. Uzoejinwa, “Simulation and experimental study of asymmetric split and recombine micromixer with,” Micro Nano Lett., pp. 2–7, (2018). 


 [35]   R. R. Gidde, P. M. Pawar, S. R. Gavali, and S. Y. Salunkhe, “Flow feature analysis of an eye shaped split and collision ( ES-SAC ) element based micromixer for lab-on-a-chip application,” Microsyst. Technol., vol.3456789,(2019). 


[36]    T. Su, K. Cheng, J. Wang, Z. Xu, and W. Dai, “A fast design method for passive micromixer with angled bend,” Microsyst. Technol., (2019). 


[37]    TF. M. White, Fluid Mechanics, 7nded., University of Rhode Island, (2009).


[38]    S. J. Kline and F. A. McClintock, “Describing Uncertainties in Single-Sample Experiments,” Mechanical Engineering, pp. 3-9, (1953).