Flow simulation of gallium in a cylindrical annulus in the presence of a magnetic field for improving the casting process
الموضوعات : فصلنامه شبیه سازی و تحلیل تکنولوژی های نوین در مهندسی مکانیک
1 - استادیار، گروه مهندسی مکانیک، واحد نجف آباد، دانشگاه آزاد اسلامی، نجف آباد، ایران.
2 - استادیار، دانشکده مهندسی مواد، واحد نجف آباد، دانشگاه آزاد اسلامی، نجف آباد، ایران.
الکلمات المفتاحية: magnetic field, Numerical simulation, Molten gallium, Casting process,
ملخص المقالة :
Free convection flow in an enclosure filled with a congealing melt leads to the product with a nonuniform structure involving large grains. The convective flows are decreased by applying an appropriate magnetic field, obtaining uniform and small grain structures. In this work, using the finite volume method, we investigated the application of a magnetic field to the convective heat transfer and temperature fields in steady and laminar flows of melted gallium in an annulus between two horizontal cylinders. The inner and outer walls of the annulus are hot and cold, respectively. Moreover, the effect of the magnetic field on the flow and temperature distribution has been investigated. The influence of the variation of other parameters including the Rayleigh number and the angle of the magnetic field on the flow and temperature field also have been studied. It has been revealed that on changing the field angle to the horizon, the Nusselt number (Nu) is increased, which is of importance in a specific range of Hartmann numbers. Also with increasing the Rayleigh number, the change in Nu with the magnetic field intensity does not occur.
[1] Sheikhzadeh G. A., Sarhaddi F., Wongwises S., Multi-objective optimization of natural convection in a cylindrical annulus mold under magnetic field using particle swarm algorithm, International Communications in Heat and Mass Transfer, 60, 2015, pp. 13-20.
[2] Afrand M., Sina N., Teimouri H., Mazaheri A., Safaei M.R., Hemmat Esfe M., Kamali J., Toghraie D., Effect of magnetic field on free convection in inclined cylindrical annulus containing molten potassium, International Journal of Applied Mechanics, 7, 2015, p. 1550052 (16 pages).
[3] Afrand M., Rostami S., Akbari M., Wongwises S., Hemmat Esfe M., Karimipour A., Effect of induced electric field on magneto-natural convection in a vertical cylindrical annulus filled with liquid potassium, International Journal of Heat and Mass Transfer, 90, 2015, pp. 418–426.
[4] Sankar M., Venkatachalappa M., Shivakumara, I.S., Effect of magnetic field on natural convection in a vertical cylindrical annulus, International Journal of Engineering Science, 44, 2006, pp. 1556–1570.
[5] Sekhar, T.V.S., Sivakumar, R., Kumar, H. and Ravi kumar, T.V.R. “Effect of aligned magnetic field on the steady viscous flow past a circular cylinder”, Applied Mathematical Modelling, Vol. 31, pp. 130–139, 2007.
[6] Kabeir S.M.M., Hakiem M.A., Rashad A.M., Group method analysis of combined heat and mass transfer by MHD non-Darcy non-Newtonian natural convection adjacent to horizontal cylinder in a saturated porous medium, Applied Mathematical Modelling, 32, 2008, pp. 2378–2395.
[7] Barletta A., Lazzari S., Magyari E., Pop, I., Mixed convection with heating effects in a vertical porous annulus with a radially varying magnetic field, International Journal of Heat and Mass Transfer, 51, 2008, pp. 5777–5784.
[8] Ishak A., Nazar R., Pop L., Magnetohydrodynamic (MHD) flow and heat transfer due to a stretching cylinder, Energy Conversion and Management, 49, 2008, 3265–3269.
[9] Kakarantzas S.C., Sarris I.E., Grecos A.P., Vlachos N.S., Magnetohydrodynamic natural convection in a vertical cylindrical cavity with sinusoidal upper wall temperature, International Journal of Heat and Mass Transfer, 52, 2009, pp. 250–259.
[10] Ellahi R., Hayat T., Mahomed F.M., Zeeshan A., Analytic solutions for MHD flow in an annulus, Communications Nonlinear Sciences Numerical Simulation, 15, 2010, pp. 1224–1227.
[11] Venkatachalappa M., Do Y., Sankar M., Effect of magnetic field on the heat and mass transfer in a vertical annulus, International Journal of Engineering Science, 49, 2011, pp. 262-278.
[12] Kuehn T.H., Goldstein R.J., An Experimental and Theoretical Study of Natural Convection in the Annulus Between Horizontal Concentric Cylinders, Journal of Fluid Mechanics, 4, 1976, pp. 695-719.
