7. Chilton-Colburn Analogy

The Reynolds analogy does not always give satisfactory results. Thus, Chilton and Colburn experimentally modified the Reynolds’ analogy. The empirically modified Reynolds’ analogy is known as Chilton-Colburn analogy. \[\text{St}\; \text{Pr}^{2/3} = \text{ Colburn $j$-factor }=j_H =\frac{f}{2}\] Valid for: \(0.6<\text{Pr}<60\).
Laminar flows: valid for \(dP/dx \approx 0\)
Turbulent flows: generally valid without restriction on \(dP/dx\).