ISSN Online: 2377-424X
International Heat Transfer Conference 12
Natural-Convective Heat Transfer from Vertical Walls of Cube and Square Prism in Air
Abstract
This communication presents the results of experimental investigations on average natural-convection heat transfer from the isothermal vertical surfaces of a cube and vertical short and slender square prisms to air. For the convective heat transfer measurements a simple lumped capacitance method was used. Results of the validation experiment performed with the short circular cylinder (H/D=1.006) showed very good agreement with the formula of McAdams recommended for flat isothermal plate (where: H, D − height and diameter of the circular cylinder). Results of average heat transfer measurements obtained for a cube were correlated with the formula: NuH=0.949*RaH0.215 in the range 1.8*104<RaH<8*105, and for vertical square prisms with the formula: NuH=1.10*RaH0.2(H/W)0.1233 in the range 1.8*104<RaH<5.5*108 and 1<H/W<21 (where: NuH − average Nusselt
number, RaH − Rayleigh number, H, W − height and width of the cube or square prisms).