抄録
An experimental study is carried out for natural-convection heat transfer to air from upward-facing and downward-facing heated circular plates under the condition that the amount of heat dissipating through the side wall of the plates is sufficiently negligible.
For the case of upward-facing plate, it is shown that in laminar flow region, the temperature distributions in air near the plate are similar when the Rayleigh numbers of the experimental runs are equal to each other. A correlation equation is proposed for the average heat transfer coefficient, with the discussion on the applicability of previously proposed equations.
Another heat transfer correlation is proposed for downward-facing plate and compared with previousily proposed experimental and theoretical correlations. Moreover, a profile method is applied to investigate the functional forms of the velocity and temperature profiles in boundary layer.
