A numerical study was undertaken on the laminar convective heat transfer from vertical polygonal cylinders with an uncovered top surface for a relatively small polygons area. The polygonal cylinders were perpendicularly placed on a flat adiabatic base plate, and uniform wall temperature boundary conditions were assumed. The governing equations for geometrical evaluation were solved numerically in terms of dimensionless variables using FLUENT. The numerical model has been validated with the existing experimental and empirical correlation equations. From the results obtained, mean Nusselt numbers from the polygonal cylinders were calculated using parameters such as the Rayleigh number ; the polygon area ; the number of sides of the polygon, ; and the Prandtl number . Results were obtained only for . Values of in the range , values of in the range to , and values of in the range 0.08 to 1 were considered. The effects of , and on the mean Nusselt number for the combined and for the individual surfaces of the polygonal cylinder are presented. Correlation equations for the mean Nusselt numbers for the side and top surfaces of the polygonal cylinders were developed.
Natural Convective Heat Transfer from Vertical Isothermal Polygonal Cylinders
Journal of Thermophysics and Heat Transfer ; 35 , 4 ; 854-868
2021-06-03
15 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch