NATURAL CONVECTION OVER BODIES IN THE TRANSITION ZONE BETWEEN LAMINAR THIN BOUNDARY LAYER DOMINATED AND CONDUCTION DOMINATED NATURAL CONVECTION

摘要

Different Rayleigh (Ra)-Nusselt (Nu)-correlations exist for natural convection from bodies. Different characteristic lengths are used by different authors. This paper reports of an experiment in which Ra is varied in an intermediate range. It is an interesting range because the values lie in a transition zone between laminar thin boundary layer dominated and conduction dominated natural convection. The experimental data is compared with existing correlations to check the accuracy and validity of these correlations for this transitional range of Ra. A new correlation that is only valid in this transitional zone is also proposed.