KoachCSR
According to the equation you wrote, you can also write ΔS = (-QH/TH) + (QL/TL) that is QH=QL=Q if we suppose a HE without losses towards ambient, so ΔS = (-Q/TH) + (Q/TL) = Q (1/TL - 1/TH) = Q (TH - TL) / (TH*TL). This states, as I said, that entropy is proportional to the mean...
thanks everyone for replies
The second law efficency basically is like KoachCSR said, the exergy, so we are referring about entropy.
in this Paint file I try to explain better what I mean. I figure A the steam condensates at costant temp and water rise temp. Entropy is proportional to the...
Hello everyone!
If I need to heat water, for example from 50° to 70° with a shell and tube HE, what is the more efficient primary fluid to be used, in terms of second law efficiency? Hot water or Steam (e.g. 3 bar). I would say hot water but I am not so sure. The system considered is only the...