Question

Relation between hydrodynamic boundary layer thickness $\delta$ and thermal boundary layer thickness ${\delta }_t$, for laminar flow over a flat plate, is

• A. $\frac{{\delta }_t}{\delta }\approx (Pr{)}^{1/3}$
• B. $\frac{\delta }{{\delta }_t}\approx (Pr{)}^{1/3}$
• C. $\delta \approx {\delta }_t$
• D. $\frac{\delta }{{\delta }_t}\approx (Pr{)}^{2/3}$

Answer 1

The correct option is B $\frac{\delta }{{\delta }_t}\approx (Pr{)}^{1/3}$

In laminar flow over a flat plate :

$\frac{\delta }{{\delta }_t}\approx (Pr{)}^{1/3}$