Heat Transfer Internal Flow Film Temperature

[eurekameh]

I have three temperatures (temperature of the fluid going in, temperature going out, and the temperature of the surface of the tube). What I'm trying to figure out is the film temperature at which I should evaluate the flow properties. The film temperature is defined as T,f = (T,s + T,infinity)/2, where T,s is the surface temperature, and T,infinity is the free-stream temperature. Am I to assume that the free-stream temperature is the same as the surface temperature, since it's not in the problem statement?

 

[Chestermiller]

The free stream temperature is T_infinity. It varies from the inlet to the exit of the tube. What physical properties of the alloy do you need to know to solve this problem?