Laminar Free and Forced magnetoconvection through an Octagonal Channel with a Heat Generating Circular Cylinder

Authors

  • Rehena Nasrin Department of Mathematics, Bangladesh University of Engineering and Technology, Dhaka
  • MA Alim Department of Mathematics, Bangladesh University of Engineering and Technology, Dhaka

DOI:

https://doi.org/10.3329/jname.v9i1.7891

Keywords:

Heat generation, circular cylinder, octagonal channel, free and forced magnetoconvection, finite element method

Abstract

In this paper, hydromagnetic flow and thermal behaviors of fluid on free and forced convection inside an octagonal vertical channel are investigated. The channel consists of a centered heat generating hollow solid circular cylinder. The vertical and inclined walls of the octagon are insulated perfectly. The input and output opening are situated at the bottom and top surface respectively. The octagon is filled with electrically conducting fluid. The integral forms of the governing equations are solved numerically using Galerkins Weighted Residual Finite Element method. Computational domains are divided into finite numbers of body fitted control volumes with collocated variable arrangement. Results are presented in the form of average Nusselt number (Nu) and maximum temperature (?max) of the fluid for a selected range of magnetic parameter Hartmann number Ha (0 - 50). Streamlines and isothermal lines are also displayed for three different values (0.1, 1 and 10) of convection parameter (Ri) and for a fluid having magnetic field. The results indicate that the highest Nu and ?max are found for the absence of Ha in all convection regions.

DOI: http://dx.doi.org/10.3329/jname.v9i1.7891

Journal of Naval Architecture and Marine Engineering 9(2012) 25-34

Downloads

Download data is not yet available.
Abstract
158
PDF
107

References

Bhoite, M. T., Narasimham, G. S. V. L. and Murthy, M. V. K (2005): Mixed convection in a shallow enclosure with a series of heat generating components, International Journal of Thermal Sciences, Vol. 44, No. 2, pp.121-135. http://dx.doi.org/10.1016/j.ijthermalsci.2004.07.003.

Brown, N. M. and Lai, F.C. (2005): Correlations for combined heat and mass transfer from an open cavity in a horizontal channel, International Communication in Heat and Mass Transfer, Vol. 32, No. 8, pp. 10001008.

Manca, O., Nardini, S. and Vafai, K. (2006): Experimental investigation of mixed convection in a channel with an Open Cavity, Experimental Heat Transfer, Vol. 19, pp. 5368.

Najam, M., Amahmid, A., Hasnaoui, M. and Alami, M. E. (2003): Unsteady mixed convection in a horizontal channel with rectangular blocks periodically distributed on its lower wall, International Journal of Heat and Fluid Flow, Vol. 24, pp. 726-735.

Nasrin, R. (2011): Finite element simulation of hydromagnetic convective flow in an obstructed cavity, International Communications in Heat and Mass Transfer, Vol. 38, No. 5, pp. 625-632. http://dx.doi.org/10.1016/j.icheatmasstransfer.2011.02.005.

Nasrin, R. (2011): Rayleigh and Prandtl number effects on free and forced magnetoconvection in a lid driven enclosure with wavy bottom wall, International Journal of Energy and Technology, Vol. 3, No. 23, pp. 1-8.

Nasrin, R. and Parvin, S. (2011): Hydromagnetic effect on mixed convection in a lid-driven cavity with sinusoidal corrugated bottom surface, International Communications in Heat and Mass Transfer, Vol. 38, No. 6, pp. 781-789. http://dx.doi.org/10.1016/j.icheatmasstransfer.2011.03.002.

Nasrin, R. and Parvin, S. (2012): Flow behavior for combined convection in a vertical channel controlled by a heat-generating tube, International Journal of Energy & Technology, Vol. 4, No. 1, pp. 1-7.

Parvin, S. and Nasrin, R. (2012): Effects of Reynolds and Prandtl number on mixed convection in an octagonal channel with a heat-generating hollow cylinder, Journal of Scientific Research, Vol.4, No.2, pp. 337-348.

Rahman, M. M., Nasrin, R. and Billah, M. M. (2010): Effect of Prandtl number on hydromagnetic mixed convection in a double-lid driven cavity with a heat-generating obstacle, Engineering e-Transaction, Vol. 5, No. 2, pp. 90-96.

Rahman, M. M., Parvin, S., Saidur, R. and Rahim, N.A. (2011): Magnetohydrodynamic mixed convection in a horizontal channel with an open cavity, International Communications in Heat and Mass Transfer, Vol. 38, pp. 184193. http://dx.doi.org/10.1016/j.icheatmasstransfer.2010.12.005.

Rao, G. M. and Narasimham, G. S. V .L. (2007): Laminar conjugate mixed convection in a vertical channel with heat generating components, International Journal of Heat and Mass Transfer, Vol. 50, No. 17-18, pp. 3561-3574.

Reddy, J. N. (1993): An Introduction to Finite Element Analysis, McGraw-Hill, New-York.

Roy, S. and Basak, T. (2005): Finite element analysis of natural convection flows in a square cavity with non uniformly heated wall(s), International Journal of Engineering Sciences, Vol. 43, pp. 668-680.

Saha, G., Saha, S., Hasan, M. N. and Islam, M .Q. (2010): Natural convection heat transfer within octagonal enclosure, IJE Transactions A: Basics, Vol. 23, No. 1, pp. 1-10.

Singh, S. and Sharif, M.A.R. (2003): Mixed convection cooling of a rectangular cavity with inlet and exit openings on differentially heated side walls, Numerical Heat Transfer, Part A, Vol. 44, pp. 233253.

Tsay, Y. L., Cheng, J. C. and Chang, T. S. (2003): Enhancement of heat transfer from surface-mounted block heat sources in a duct with baffles, Numerical Heat Transfer, Part A, Vol. 43, pp. 827-841.

Zeinkiewicz, O. C., Taylor, R. L. and Too, J. M. (1971): Reduced integration technique in general analysis of plates and shells, International Journal for Numerical Methods in Engineering, Vol. 3, pp. 275-290. http://dx.doi.org/10.1002/nme.1620030211.

Downloads

Published

26.05.2012

How to Cite

Nasrin, R., & Alim, M. (2012). Laminar Free and Forced magnetoconvection through an Octagonal Channel with a Heat Generating Circular Cylinder. Journal of Naval Architecture and Marine Engineering, 9(1), 25–34. https://doi.org/10.3329/jname.v9i1.7891

Issue

Section

Articles

Most read articles by the same author(s)