An analytical study has been made of how the circumferential distribution of the wall heat flux affects the forced/natural convection flow and heat transfer in a horizontal tube. Two heating conditions were investigated, one in which the tube was uniformly heated over the top half and insulated over the bottom, and the other in which the heated and insulated portions were reversed. The results were obtained numerically for a wide range of the governing buoyancy parameter and for Prandtl numbers of 0.7 and 5. It was found that bottom heating gives rise to a vigorous buoyancy-induced secondary flow, with the result that the average Nusselt numbers are much higher than those for pure forced convection, while the local Nusselt numbers are nearly circumferentially uniform. A less vigorous secondary flow is induced in the case of top heating because of temperature stratification, with average Nusselt numbers that are substantially lower than those for bottom heating and with large circumferential variations of the local Nusselt number. The friction factor is also increased by the secondary flow, but much less than the average heat transfer coefficient. It was also demonstrated that the buoyancy effects are governed solely by a modified Grashof number, without regard for the Reynolds number of the forced convection flow.
Skip Nav Destination
Article navigation
Research Papers
Effect of Circumferentially Nonuniform Heating on Laminar Combined Convection in a Horizontal Tube
S. V. Patankar,
S. V. Patankar
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
Search for other works by this author on:
S. Ramadhyani,
S. Ramadhyani
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
Search for other works by this author on:
E. M. Sparrow
E. M. Sparrow
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
Search for other works by this author on:
S. V. Patankar
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
S. Ramadhyani
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
E. M. Sparrow
Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minn.
J. Heat Transfer. Feb 1978, 100(1): 63-70 (8 pages)
Published Online: February 1, 1978
Article history
Received:
April 22, 1977
Online:
August 11, 2010
Connected Content
Citation
Patankar, S. V., Ramadhyani, S., and Sparrow, E. M. (February 1, 1978). "Effect of Circumferentially Nonuniform Heating on Laminar Combined Convection in a Horizontal Tube." ASME. J. Heat Transfer. February 1978; 100(1): 63–70. https://doi.org/10.1115/1.3450505
Download citation file:
Get Email Alerts
Cited By
Local Heat Transfer Distribution on Thin Metal Foil Impinged by Array of Free Surface Jets
J. Heat Mass Transfer (July 2024)
Instability of Jeffrey Fluid Throughflow in a Porous Layer Induced by Heat Source and Soret Effect
J. Heat Mass Transfer (July 2024)
Related Articles
Bouyancy Effect on Forced Convection in Vertical Tubes at High Reynolds Numbers
J. Thermal Sci. Eng. Appl (December,2010)
An Experimental Study of Forced Heat Convection in Concentric and Eccentric Annular Channels
J. Heat Transfer (January,2016)
Forced Convection Heat Transfer in Channels With Rib Turbulators Inclined at 45 deg
J. Turbomach (April,2009)
Uneven Wall Heat Flux Effect on Local Heat Transfer in Rotating Two-Pass Channels With Two Opposite Ribbed Walls
J. Heat Transfer (November,1996)
Related Chapters
Mixed-Up Convection
Hot Air Rises and Heat Sinks: Everything You Know about Cooling Electronics Is Wrong
Hydraulic Resistance
Heat Transfer & Hydraulic Resistance at Supercritical Pressures in Power Engineering Applications
The Design and Implement of Remote Inclinometer for Power Towers Based on MXA2500G/GSM
International Conference on Mechanical and Electrical Technology, 3rd, (ICMET-China 2011), Volumes 1–3