Ren C m Values for C and m 1-40 0.75 0.4 40-1000 051 05 103-2×10° 0.26 0.6 2×10-10r 0.076 0.7 Expect accuracy within 20%with these correlations The empirical correlation due to Hilpert NuD≡ hD=CRepPr Values of C and m are listed in Table 7.2. All properties are evaluated at the film temperature #10 Heat Transfer Su Yongkang School of Mechanical EngineeringHeat Transfer Su Yongkang School of Mechanical Engineering # 10 • Values for C and m • Expect accuracy within  20% with these correlations • The empirical correlation due to Hilpert • Values of C and m are listed in Table 7.2. • All properties are evaluated at the film temperature. 1/3 Re Pr m D C D k hD Nu  