پیوندهای مفید
آمار
| تعداد نشریات | 21 |
| تعداد شماره‌ها | 635 |
| تعداد مقالات | 9,313 |
| تعداد مشاهده مقاله | 67,881,137 |
| تعداد دریافت فایل اصل مقاله | 17,081,860 |
Numerical simulation of Laminar Free Convection Heat Transfer around Isothermal Concave and Convex Body Shapes | ||
| Journal of Heat and Mass Transfer Research | ||
| مقاله 4، دوره 2، شماره 2 - شماره پیاپی 4، بهمن 2015، صفحه 37-44 اصل مقاله (1.21 M) | ||
| نوع مقاله: Full Length Research Article | ||
| شناسه دیجیتال (DOI): 10.22075/jhmtr.2015.349 | ||
| نویسندگان | ||
| Sayed Mohammad Hashem Jayhooni* 1؛ Khosrow Jafarpur2 | ||
| 1School of Mechanical Engineering, Shiraz University, Shiraz, Iran | ||
| 2School of Mechanical Engineering, Shiraz University, Shiraz, Iran. | ||
| تاریخ دریافت: 04 بهمن 1392، تاریخ بازنگری: 25 خرداد 1393، تاریخ پذیرش: 09 دی 1394 | ||
| چکیده | ||
| In the present research, free convection heat transfer from isothermal concave and convex body shapes is studied numerically. The body shapes investigated here, are bi-sphere, cylinder, prolate and cylinder with hemispherical ends; besides, they have the same height over width (H/D = 2). A Numerical simulation is implemented to obtain heat transfer and fluid flow from all of the geometries in a wide range of Rayleigh numbers. The results show that flatness, concavity and smoothness have major effects on estimation of free convection heat transfer. As the total surface heat transfer area changed by altering the geometry, the local Nusselt number are compared for these body shapes; as well; it shows that concave surfaces has adverse influence on transferring heat. In addition, the current results reveal the average Nusselt numbers based on square surface area are not affected by the geometries for the laminar range of Rayleigh numbers. Besides, “incompressible ideal gas model” is used for the variation of density in free convection heat transfer. This model has the capability to be utilized in the cases with high temperature differences between the fluid and the bodies’ surfaces. | ||
| کلیدواژه‌ها | ||
| Free convection؛ Concave surface؛ Convex surface؛ Numerical simulation | ||
| مراجع | ||
|
[1] O.G. Martynenko, P.P. Khramtsov, Free-Convective Heat Transfer, Springer, Heidelberg, (2005). [2] M.J. Chamberlain, Free Convection Heat Transfer from a Sphere, Cube and Vertically Aligned Bi-Sphere, M.S. Thesis, Dept. Mech. Eng., University of Waterloo, Waterloo, Canada, (1983). [3] E.M. Sparrow, A.J. Stretton, Natural convection from variously oriented cubes and from other bodies of unity aspect ratio, International Journal of Heat and Mass Transfer, 28, 741-752, (1985). [4] M.M. Yovanovich, K. Jafarpur, Models of Laminar Natural Convection from Vertical and Horizontal Isothermal Cuboids for all Prandtl Numbers and All Rayleigh Numbers Below 1011, Fundamentals of Natural Convection, ASME HTD, 264, 111 - 126, (1993). [5] M. Eslami, K. Jafarpur, M.M. Yovanovich, Laminar Natural convection Heat Transfer from Isothermal Cones with Active End, Iranian Journal of Science and Technology, Transaction B, Engineering, 33(B3), 217-229, (2009). [6] M. Eslami, K. Jafarpur, Laminar natural convection heat transfer from isothermal cylinders with active ends, Heat Transfer Engineering, 32, 506–513, (2011). [7] M.M. Yovanovich, On the effect of shape, aspect ratio and orientation upon natural convection from isothermal bodies of complex shape, ASME HTD, 82, 121–129, (1987). [8] A.V. Hassani, K.G.T. Hollands, On natural convection heat transfer from three-dimensional bodies of arbitrary shape, ASME Journal of Heat Transfer, 111, 363–371, (1989). [9] S. Lee, M.M. Yovanovich K. Jafarpur, Effects of geometry and orientation on laminar natural convection from isothermal bodies, Journal of Thermophysics and Heat Transfer, 5, 208–216, (1991). [10] K. Jafarpur, Analytical and experimental study of laminar free convective heat transfer from isothermal convex bodies of arbitrary shape, PhD thesis, University of Waterloo, Waterloo, Canada, (1992). [11] M. Eslami, K. Jafarpur, Laminar Free Convection Heat Transfer From Isothermal Convex Bodies of Arbitrary Shape: A New Dynamic Model, Heat and Mass Transfer, 48(2), 301-315, (2012). [12] K. Kishinami, H. Saito, I. Tokura, An experimental study on natural convection heat transfer from the vertical wavy surface heated at convex/concave elements, Experimental Thermal and Fluid Science. 36, 305-315, (1989). [13] M. Kumari, I. Pop, H.S. Takhar, Free-convection boundary-layer flow of a non-Newtonian fluid along a vertical wavy surface, International Journal of Heat and Fluid Flow, 18, 625–631, (1997). [14] E. Kim, Natural convection along a wavy vertical plate to non-Newtonian fluids, International Journal of Heat and Mass Transfer, 40, 3069–3078, (1997). [15] S.U. Rahman, Natural convection along vertical wavy surfaces: an experimental study, Chemical Engineering Journal, 84, 587–591, (2001). [16] J. Jer-Huan, Y. Wei-Mon, L. Hui-Chung, Natural convection heat and mass transfer along a vertical wavy surface, International Journal of Heat and Mass Transfer, 46, 1075–1083, (2003). [17] J. Jer-Huan, Y. Wei-Mon, Transient analysis of heat and mass transfer by natural convection over a vertical wavy surface, International Journal of Heat and Mass Transfer, 47 3695–3705, (2004). [18] Y. Lun-Shin, Natural convection along a vertical complex wavy surface, International Journal of Heat and Mass Transfer, 49, 281–286, (2006). [19] I. Pop, T.Y. Na, Natural convection from a wavy cone, Applied Scientific Research 54(2), 125-136, (1995). [20] I. Pop, T.Y. Na, Natural convection over a vertical wavy frustum of a cone, International Journal of Non-Linear Mechanics, 34(5), 925-934 , (1999). [21] M.A. Hossain , M.S. Munir, I. Pop, Natural convection flow of a viscous fluid with viscosity inversely proportional to linear function of temperature from a vertical wavy cone, International Journal of Thermal Science, 40(4), 366–371, (2001). [22] A. Rahman, M.M. Molla, M.M.A. Sarker, Natural convection flow along the vertical wavy cone in case of uniform surface heat flux where viscosity is an exponential function of temperature, International Communications in Heat and Mass Transfer, 38, 774–780, (2011). [23] J.M. Khubeiz, E. Radziemska, W.M. Lewandowski, Natural convective heat-transfers from an isothermal horizontal hemispherical cavity, Applied Energy 73, 261–275, (2002). [24] S.V. Patankar, Numerical Heat Transfer and Fluid Flow. Hemisphere, Washington DC, (1980). [25] A.V. Hassani, An Investigation of Free Convection Heat Transfer from Bodies of Arbitrary Shape, Ph.D. thesis, University of Waterloo, Waterloo, ON, Canada, (1987). | ||
|
آمار تعداد مشاهده مقاله: 2,862 تعداد دریافت فایل اصل مقاله: 2,064 |
||