Question

Air enters a thin-walled, 5-mm diameter, 2-m-long tube at a uniform inlet temperature of 100°C. A constant heat flux is applied to the air from the tube surface. The mean temperature of air at halfway along the tube (at 1 m length) is reported as 126°C. If the tube surface temperature at the exit is 160°C and the local heat transfer coefficient at the exit is 29.5 W/m^2K, determine

a) the applied heat flux,

b) the rate of energy increase in air from the entrance to the exit of the tube,

c) the mass flow rate of air in the tube,

d) the local heat transfer coefficient at halfway along the tube (at 1 m length),

e) the surface temperature of the tube at halfway along the tube (at 1 m length).

Assume steady-state conditions and constant air properties.

Answer 1