Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30855
Analyses of Natural Convection Heat Transfer from a Heated Cylinder Mounted in Vertical Duct

Authors: H. Bhowmik, A. Faisal, Ahmed Al Yaarubi, Nabil Al Alawi


Experiments are conducted to analyze the steady-state and the power-on transient natural convection heat transfer from a horizontal cylinder mounted in a vertical up flow circular duct. The heat flux ranges from 177 W/m2 to 2426 W/m2 and the Rayleigh number ranges from 1×104 to 4.35×104. For natural air flow and constant heat flux condition, the effects of heat transfer around the cylinder under steady-state condition are investigated. The steady-state results compare favorably with that of the available data. The effects of transient heat transfer data on different angular position of the thermocouple (0o, 90o, 180o) are also reported. It is observed that the transient heat transfer around the cylinder is strongly affected by the position of thermocouples. In the transient region, the rate of heat transfer obtained at 90o and 180o are higher than that of stagnation point (0o). Finally, the dependence of the average Nusselt number on Rayleigh number for steady and transient natural convection heat transfer are analyzed, and a correlation equation is presented.

Keywords: natural convection, transient, Rayleigh number, nusselt number, steady-state, Fourier number

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 661


[1] M. S. Sadeghipour, and M. Asheghi, “Free convection heat transfers from arrays of vertically separated horizontal cylinders at low Rayleigh numbers,” Int. J. Heat Mass Transf, vol. 37, pp. 103-109, 1994.
[2] A. Hatton, and D. James, “H. Swire, Combined forced and natural convection with low-speed air flow over horizontal cylinders,” J. Fluid Mech., vol. 42, pp. 17–31, 1970.
[3] E. Weder, “Messung des gleichzeitigen Wärme- und stoffübergangs am horizontalen Zylinder bei freier Konvecktion,” Wärme Stoffübergangs, vol. 1, pp. 10–14, 1968.
[4] V. Morgan, “The overall convective heat transfers from smooth circular cylinders,” Adv. Heat Transf, vol. 11, pp. 199-269, 1975.
[5] T. H. Kuehn, and R. J. Goldstein, “Numerical solution to the Navier-Stokes equations for laminar natural convection about a horizontal isothermal circular cylinder,” Int. J. Heat Mass Transf., vol. 23, pp. 971-979, 1980.
[6] T. Saitoh, T. Sajiki, and K. Maruhara, “Bench mark solutions to natural convection heat transfer problem around a horizontal circular cylinder,” Int. J. Heat Mass Transf., vol. 36, pp. 1251-1259, 1996.
[7] P. Wang, R. Kahawita, and T. Nguyen, “Numerical computation of the natural convection flow about a horizontal cylinder using splines,” Numer. Heat Transf., vol. 17, pp. 191–215, 1990.
[8] Z. Qureshi, “Ahmad R., “Natural convection from a uniform heat flux horizontal cylinder at moderate Rayleigh numbers,” Numer. Heat Transf., vol. 11, pp. 199–212, 1987.
[9] R. Chouikh, A. Guizani, M. Maalej, and A. Belghith, “Numerical study of the laminar natural convection flow around horizontal isothermal cylinder. Renew,” Energy, vol. 13, pp. 77–88, 1998.
[10] R. J. Goldstein, and D. G. Briggs, “Transient free convection about vertical plates and cylinders,” Trans. ASME J. Heat Trans., vol. 49, pp. 500, 1964.
[11] O. F. Genceli, “The onset of manifest convection from suddenly heated horizontal cylinders,” Wdrme- und Stofltibertr, vol. 13, pp. 163-169, 1980.
[12] S. Özgür Atayılmaz, “Transient and steady-state natural convection heat transfer from a heated horizontal concrete cylinder,” Int. J. Therm Sci., vol. 49, pp. 1933-1943, 2010.
[13] M. S. Sadeghipour, and S. K. Hannani, “Transient Natural Convection from a Horizontal Oriental Cylinder Confined between Vertical Walls- A Finite Element Solutions,” Int. J. Num. Methods in Engg., vol. 34, pp. 621-635, 1992.
[14] B. Sammakia, B. Gebhart, and Z. H. Qureshi, “Measurements and calculations of transient natural convection in water,” Trans. ASME J. Heat Trans., vol. 104, pp. 644-648, 1982.
[15] A. S. Gupta, and I. Pop, “Effects of curvature on unsteady free convection past a circular cylinder,” Physics Fluid, vol. 20, pp. 162-163, 1977.
[16] L. Elliott, “Free convection on a two dimensional or axisymmetric body,” Q. J. Mech. Appl. Math., vol. 23, pp. 153-162, 1970.
[17] J. H. Merkin, “Free convection boundary layers on cyl- inders of elliptic cross section,” Trans. ASME J. Heat Trans, vol. 99, pp. 453-457, 1977.
[18] B. Farouk, and S. I. Guceri, “Natural convection from a horizontal cylinder-laminar regime,” Trans. ASME J. Heat Trans., vol. 103, pp. 522-527, 1981.
[19] J. R. Parsons, and J. C. Mulligan, “Transient Free Convection from a Suddenly Heated Horizontal Wire,” Trans. ASME J. Heat Trans., vol. 100, pp. 423-428, 1978.
[20] H. Bhowmik, and K. W. Tou, “Experimental study of transient natural convection heat transfer from simulated electronic chips,” Exp. Ther. Fluid Sci., vol. 29, pp. 485-492, 2005.
[21] C. J. Greankoplis, “Massa Transport Phenomena,” Holt, Rinehart & Winston, New York, 1972.
[22] H. K. Jong, and W. Terrence, “Simon, Raymond V., Journal of Heat Transfer Policy on Reporting Uncertainties in Experimental Measurements and Results,” Trans. ASME J. Heat Transf., vol. 115, pp. 5-6, 1993.
[23] Y. Varol, E. Avci, A. Koca, and H. F. Oztop, “Prediction of flow fields and temperature distributions due to natural convection in a triangular enclosure using Adaptive- Network-Based Fuzzy Inference System (ANFIS) and Artificial Neural Network (ANN),” Int. Commun. Heat Mass Transf., vol. 34, pp. 887–896, 2007.