Advertisement

Heat and Mass Transfer

, Volume 52, Issue 3, pp 611–619 | Cite as

Numerical analysis of lamination effect in a vortex micro T-mixer with non-aligned inputs

Original

Abstract

In the present study, the lamination effect in a micro T-mixer with non-aligned inputs on the mixing index has been investigated numerically in four different cases. The multi-block lattice Boltzmann method has been implemented for the flow field simulation and the second order upwind finite difference scheme has been used to simulate mass transfer. Reynolds numbers includes in the range of 10 ≤ Re ≤ 70. The simulation results show that the lamination effect in the mixer inputs, despite of its simple design, causes the interface of two fluids to increase and also to make the vortex effect stronger in the confluence of two fluid streams that increases the mixing index considerably. Of four lamination cases included for the mixing input, the maximum mixing index is for the vertical and asymmetrical lamination at the Reynolds number of 70 that is equal 0.689 and the minimum mixing index is for the horizontal and asymmetrical lamination at the Reynolds number of 10 that is equal 0.198.

Keywords

Vortex Reynolds Number Lamination Recirculation Zone Lattice Boltzmann Method 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

C

Mass-fraction

C1

Water mass-fraction

C2

Ethanol mass-fraction

D

Diffusivity of water and ethanol

Dh

Hydraulic diameter

H

Characteristic length

P

Dimensionless pressure

Re

Reynolds number

Sc

Schmit number

U, V, W

Dimensionless velocity

\(\vec{V}\)

Velocity vector

X, Y, Z

Dimensionless directions

\(\vec{e}_{i}\)

Lattice speed vector in the link of ith

\(f_{i}\)

Velocity distribution function

\(\tilde{f}_{i}\)

Post-collision distribution function

\(f_{i}^{eq}\)

Equilibrium distribution function

p

Mean static pressure (Pa)

\(\vec{r}\)

Location vector

x, y, z

Cartesian directions

Greek symbols

σ

Variance

\(\tau_{v}\)

Velocity relaxation time

ν

Kinematic viscosity (m2/s)

\(\omega_{i}\)

Weighting coefficient

\(\varGamma\)

Non-dimensional circulation

\(\zeta_{z}\)

Vorticity in the z direction

References

  1. 1.
    Ho CM, Tai YC (1998) Micro-electro-mechanical systems (MEMS) and fluid flows. Annu Rev Fluid Mech 30:579–612CrossRefGoogle Scholar
  2. 2.
    Erickson D, Li DQ (2004) Integrated microfluidic devices. Anal Chim Acta 507:11–26CrossRefGoogle Scholar
  3. 3.
    Schönfeld F, Hessel V, Hofmann C (2004) An optimized split-and-recombine micromixer with uniform chaotic mixing. Lab Chip 4:65–69CrossRefGoogle Scholar
  4. 4.
    Torré JP, Fletcher DF, Lasuye T, Xuereb C (2008) An experimental and CFD study of liquid jet injection into a partially baffled mixing vessel: a contribution to process safety by improving the quenching of runaway reactions. Chem Eng Sci 63:924–942CrossRefGoogle Scholar
  5. 5.
    Saatdjian E, Rodrigo AJS, Mota JPB (2012) On chaotic advection in a static mixer. Chem Eng J 187:289–298CrossRefGoogle Scholar
  6. 6.
    Chang CC, Yang YT, Yen TH, Chen CK (2009) Numerical investigation into thermal mixing efficiency in Y-shaped channel using Lattice Boltzmann method and field synergy principle. Int J Therm Sci 48:2092–2099CrossRefGoogle Scholar
  7. 7.
    Kwon S, Lee J (2008) Mixing efficiency of a multilamination micromixer with consecutive recirculation zones. Chem Eng Sci 64:1223–1231Google Scholar
  8. 8.
    Miranda JM, Oliveira H, Teixeira JA, Vicente AA, Correia JH, Minas G (2010) Numerical study of micro mixing combining alternate flow and obstacles. Int Commun Heat Mass 37:581–586CrossRefGoogle Scholar
  9. 9.
    Afzal A, Kim K (2012) Passive split and recombination micromixer with convergent–divergent walls. Chem Eng J 203:182–192CrossRefGoogle Scholar
  10. 10.
    Conlisk K, O’Connor GO (2012) Analysis of passive microfluidic mixers incorporating 2D and 3D baffle geometries fabricated using an excimer laser. Microfluid Nanofluid 12(6):941–951CrossRefGoogle Scholar
  11. 11.
    Ansari MA, Kim KY, Anwar K, Kim SM (2012) Vortex micro T-mixer with non-aligned inputs. Chem Eng J 181–182:846–850CrossRefGoogle Scholar
  12. 12.
    Galletti C, Roudgar M, Brunazzi E, Mauri R (2012) Effect of inlet conditions on the engulfment pattern in a T-shaped micro-mixer. Chem Eng J 185–186:300–313CrossRefGoogle Scholar
  13. 13.
    Lin Y, Yu X, Wang Z, Tu ST, Wang Z (2011) Design and evaluation of an easily fabricated micromixer with three-dimensional periodic perturbation. Chem Eng J 171:291–300CrossRefGoogle Scholar
  14. 14.
    Hossain S, Husain A, Kim KY (2010) Shape optimization of a micromixer with staggered-herringbone grooves patterned on opposite walls. Chem Eng J 162:730–737CrossRefGoogle Scholar
  15. 15.
    Ansari MA, Kim KY, Anwar K, Kim SM (2010) A novel passive micromixer based on unbalanced splits and collisions of fluid streams. J Micromech Microeng 20:055007CrossRefGoogle Scholar
  16. 16.
    Cortes-Quiroz CA, Azarbadegan A, Zangeneh M (2014) Evaluation of flow characteristics that give higher mixing performance in the 3-D T-mixer versus the typical T-mixer. Sens Actuators B Chem 202:1209–1219CrossRefGoogle Scholar
  17. 17.
    Andreussi T, Galletti C, Mauri R, Simone C, Salvetti MV (2015) Flow regimes in T-shaped micro-mixers. Comput Chem Eng 76:150–159CrossRefGoogle Scholar
  18. 18.
    Yu D, Mei R, Shyy W (2002) A multi-block lattice Boltzmann method for viscous fluid flows. Int J Numer Methods Fluids 39:99–120CrossRefMATHGoogle Scholar
  19. 19.
    Ferziger JH, Peric M (2012) Computational methods for fluid dynamics, 3rd edn. Springer, Berlin, HeidelbergGoogle Scholar
  20. 20.
    Azwadi CSN, Tanahashi T (2008) Development of 2-D and 3-D double-population thermal lattice Boltzmann models. Matematika 24(1):53–66Google Scholar
  21. 21.
    Jung S, Phares DJ, Srinivasa AR (2013) A model for tracking inertial particles in a lattice Boltzmann turbulent flow simulation. Int J Multiph Flow 49:1–7CrossRefGoogle Scholar
  22. 22.
    Krafczyk M, Cerrolaza M, Schulz M, Rank E (1998) Analysis of 3D transient blood flow passing through an artificial aortic valve by lattice-Boltzmann methods. J Biomech 31:453–462CrossRefGoogle Scholar
  23. 23.
    Mei R, Shyy W, Yu D, Luo LS (2000) Lattice Boltzmann method for 3-D flows with curved boundary. J Comput Phys 161(2):680–699CrossRefMATHGoogle Scholar
  24. 24.
    XueLin T, YanWen S, FuJun W, LinWei L (2002) Numerical research on lid-driven cavity flows using a three-dimensional lattice Boltzmann model on non-uniform meshes. Sci China Ser E Technol Sci 56(9):2178–2187Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringYazd UniversityYazdIran

Personalised recommendations