# UNSTEADY MAGNETOHYDRODYNAMIC MIXED CONVECTION FLOW WITH HEAT AND MASS TRANSFER OVER A HORIZONTAL CIRCULAR CYLINDER EMBEDDED IN A POROUS MEDIUM

## Main Article Content

## Abstract

The objective of the present study is to investigate the effect of flow parameters on the mixed convection heat and mass transfer of an unsteady magnetohydrodynamic flow of an electrically conducting, viscous, and incompressible fluid over a horizontal circular cylinder embedded in porous medium, considering effects of chemical reaction and heat source/sink, by taking into account viscous dissipation. The present magnetic field is homogenous and perpendicular to the body surface. Magnetic Reynolds number is significantly lower than one i. e. considered the problem is in approximation without induction. The governing nonlinear partial differential equations and associated boundary conditions are made dimensionless using a suitable similarity transformation and similarity parameters. System of non-dimensionless equations are solved numerically by implicit finite difference three-diagonal and iteration method. Numerical results obtained for different values of porous medium, magnetic, diffusion and temperature parameters, buoyancy diffusion parameter and thermal parameter and for different values Prandtl, Echart, and Schmidt numbers. Variation of velocity, temperature and concentration and many integral and differential characteristics boundary layer are discussed and shown graphically.

## Article Details

**Thermal Science**, [S.l.], v. 20, p. S1381-S1390, feb. 2017. ISSN 2334-7163. Available at: <http://thermal-science.tech/journal/index.php/thsci/article/view/1657>. Date accessed: 18 oct. 2017. doi: https://doi.org/10.2298/TSCI16S5381B.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Authors retain copyright of the published article and have the right to use the article in the ways permitted to third parties under the - Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International (CC BY-NC-ND) licence. Full bibliographic information (authors, article title, journal title, volume, issue, pages) about the original publication must be provided and a link must be made to the article's DOI.

The authors and third parties who wish use the article in a way not covered by the the -Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International (CC BY-NC-ND) licence must obtain a written consent of the publisher. This license allows others to download the paper and share it with others as long as they credit the journal, but they cannot change it in any way or use it commercially.

Authors grant to the publisher the right to publish the article, to be cited as its original publisher in case of reuse, and to distribute it in all forms and media.

Accepted 2017-02-07

Published 2017-02-07

## References

[2] Sparrow, E., Cess, R., Effect of Magnetic Field on Free Convection Heat Transfer, Int. J. Heat and Mass Transfer, 3 (1961), 4, pp. 267-274

[3] Rajeswari, R., et al., Chemical Reaction, Heat and Mass Transfer on Non-Linear MHD Boundary Layer Flow Through a Vertical Porous Surface in the Presence of Suction, Applied Mathematical Sciences, 3 (2009), 49-52, pp. 2469-2480

[4] Rosow, J., On Flow of Electrically Conducting Fluid over a Flat Plate in the Presence of a Transverse Magnetic field, Report No. 1358, NASA, USA, 1958

[5] Sharma, P., Singh, G., Effects of Variable Thermal Conductivity and Heat Source/Sink on MHD Flow Near Stagnation Point on a Linearly Stretching Sheet, Journal of Applied Fluid Mechanics, 2 (2009), 1, pp. 13-21

[6] Boricic, Z., et al., Universal Equations of Unsteady Two-Dimensional MHD Boundary Layer on the Body with Temperature Gradient along Surface, WSEAS Transactions on Fluid Mechanics, 4 (2009), 1, pp. 97-106

[7] Miraj, A., et al., Conjugate Effects of Radiation and Joule Heating on MHD Free Convection Flow Along a Sphere with Heat Generation, American Journal of Computational Mathematics, 1 (2011), 1, ID 4449

[8] Nikodijević, D., et al. Parametric Method for Unsteady Two-Dimensional MHD Boundary Layer on the whose Temperature Varies with Time, Archives of Mechanics, 63 (2011), 1, pp. 57-76

[9] Yih, K., Effect of Uniform Blowing/Suction on MHD Natural Convection over a Horizontal Cylinder: UWT or UHT, Acta Mechanica, 144 (2000), 1-2, pp. 17-27

[10] Aldoss, T. K., et al., MHD Mixed Convection from a Horizontal Circular Cylinder, Numerical Heat Transfer, 30 (1996), 4, pp. 379-396

[11] Boričić, A., et al., MHD Dynamics and Diffusion Boundary Layer Flow of Variable Electrical Conductivity Past a Circular Cilynder, Proceedings, SIMTERM, Soko Banja, Serbia, pp. 508-517, 2011

[12] Boričić, A., et al., MHD Effects on Unsteady Dynamic, Thermal and Diffusion Boundary Layer Flow a Circular Cilynder, Thermal Science, 12 (2012), Suppl. 2, pp. S295-S309

[13] Boričić, A., et al., Heat and Mas Transfer on Unstedy MHD Dynamics, Temperature and Diffusion Boundary Layer over a Horizontal Circular Cylinder, Proceedings, 2nd International Conference of Mechanical Engineering in XXI Century, Nis, Serbia, 2013, pp. 145-150

[14] Ingham, D., Pop, I., Natural Convection about a Haeted Horizontal Cylinder in a Porous Medim, Journal of fluid Mechanics, 184 (1987), Nov., pp. 157-181

[15] Layeghi, M., Nouri-Borujerdi, A., Darcy Model for the Study of Fluid Flow and Heat Transfer Around a Cylinder Embedded in Porous Media, International Journal for Computational Methods in Engineering Science and Mechanics, 7 (2006), 5, pp. 323-329

[16] Uddin, Z., Kumar, M., Effect of Temperature Dependent Properties on MHD Free Convection Flow and Heat Transfer Near the Lower Stagnation Point of a Porous Isothermal Cylinder, Computer Modeling and New Technologies, 13 (2009), 4, pp. 15-20

[17] Aldoss, T., Ali, Y., MHD Mixed Convection form a Horizontal Cylinder in a Porous Medium. JSME International Journal, Series B: Fluids and Thermal Engineering, 40 (1997), 2, pp. 290-295