Empirical Correlations Typical correlations for heat transfer coefficient developed from experimental data are expressed as hl CRa L k L RO G 8B(T,-T)L3 AL=ori 1/4 For T n=1/3 For L Rayleigh number Vertical plate For an plate at constant Ts Coordinales or recommended curve 1 ⊥.9 2.63 3.89 6.03 0.5 Logo NuL, 1.5 33.1 108 14 501.0 11 1.0 .2 Log1o rar Heat Transfer Su Yongkang School of Mechanical EngineeringHeat Transfer Su Yongkang School of Mechanical Engineering # 3 Empirical Correlations • Typical correlations for heat transfer coefficient developed from experimental data are expressed as: Vertical Plate For an plate at constant Ts ( )   3 Pr g T T L Ra Gr s L L −  =  = Log10RaL Log10NuL n L CRaL k hL Nu = = Rayleigh number    = = 1/ 3 1/ 4 n n For T For L