Chapter 8: Internal Forced Convection

Thermal Entrance Region• Consider a fluid at a uniform temperature entering a circular tubewhose surface is maintained at a different temperature.• Thermal boundary layer along the tube is developing.• The thickness of this boundary layer increases in the flowdirection until the boundary layer reaches the tube center.• Thermal entrance region.• Thermally fully developed region the region beyond thethermal entrance region in which the dimensionless temperatureprofile expressed as(T s -T)/(T s -T m )remains unchanged.