A circular pipe with 5-cm diameter carries a hydrodynamic fully developed flow of air. The air temperature is uniform at 300 K. Starting at a location designated with axial coordinate x = 0, where...

A circular pipe with 5-cm diameter carries a hydrodynamic fully developed flow of air. The air temperature is uniform at 300 K. Starting at a location designated with axial coordinate x = 0, where pressure is equal to 2 bars, a uniform wall temperature of 400 K is imposed. Using the solution of Notter and Sleicher (1972), calculate the local heat transfer coefficient at x = 16 cm. Compare the results with the predictions of the thermally developed correlation of Petukhov (1970) [Eqs. (7.3.33)–(7.3.35)]. Assume, for simplicity, that the Reynolds number remains constant at Re_D
= 2 × 10⁴.