Homework Statement
We're currently studying steady state one dimensional conduction heat transfer. We've touched on some surface convection, resistances in layers and fins.
I don't think I'll have much issue with this problem once I find this out:
What is a thermal driving force?
Just as a heads up, the finished integral for work for a polytropic process turns out to be pretty simple.
for p(v^n)=c
P=pressure
v=specific volume
W/m=(P2v2-P1v1)/(1-n)
You know what, based on the information given, I would let velocity drop out as well. In a basic thermo class most prevalent place you're going to see velocity -not- being negligible is in nozzle and diffuser problems, or where it is expressively given to you in the problem statement.
I would treat this as a steady state problem. Meaning your mass flow rate in is going to equal your mass flow rate out. and de/dt is zero.
Since we're not given any sorts of elevation, the potential energy will be drop out. No work is happening, so W will also drop out.
You will be...
Well, if you look at it from a first law perspective for one of the streams.
Q=m(h(out)-h(in)) If you decrease m, regardless of the factors of h, Q will decrease.
Closed system, control mass.
What you're going to want to do is model both objects as incompressible.
ca=specific heat aluminum
ci=specific heat iron
m=mass
Tf=temp final
Ti=temp Fe
Ta=temp Al
Imcompressible 1st Law
U=Q-W Q=0, W=0
U=0
U=m*c*(T2-T1)
so
Ui+Ua=0
then...