Owen Lucas wrote: > I have some questions! > > 1 Is the temperature of the pipe wall constant or is it varying along > its length. It says that is 30deg C above the mean air temperature but > is this the temperature at that point or is it 30 deg about the mean air > inlet temperature it 230 deg C.
Everything is at that point. You aren't told where the inlet is after all. > 2 Does the answer need to be done from first principals? Depends how clever you first year engineering students are ;-) Anyway, it transpires that the flow has a Reynolds number of 36000, so the flow will be fully turbulent anyway. I suspect you'll receive a prize if you can solve the Navier-Stokes equations analytically. Here they have been told of correlations valid for fully developed pipe flow that give Nusselt number as a function of Reynolds number and Prandtl number. -- Angus
