Hi All
I have an insulated composite wall. I know all of the thicknesses, K values and the inner wall temperature T1. How do I determine the outer wall temperature, T2, if I don't know the heat transfer rate Q?
Thanks in advance for all of your help.
Yes, you are right with given information in problem you might end up with 1 equation 2 unknowns. But if you are allowed to make engineering guess like ambient temp at right side as standard room temperature T1=25°C. Then you can solve the problem? In that case
Q = T5-T1/(Sum of all Rth)
Also, as you said convective heat transferred can be equated to this Q dot as there is no way of generating heat inside composite wall. But in that case if you want to use Newton's equation Q=hA(Ts-Tamb). You may not know 'h' value.
I could have commented better if you posted the entire problem :)
Hello,
Welcome to thermodynamics forum :)
Regarding your question, is the inner wall temperature given or known. This problem can be solved using thermal resistance network. If inner wall temperature is not given then the final answer will be a relation between inner wall temperature and outer wall temperature.