Problem: An evaporator has R-410a at -20 C and quality 20% flowing in, with the exit flow being saturated vapor at -20 C. Consider the heating to be a reversible process and find the specific heat transfer from the entropy equation.

Question

aaronq · Answer

what does 20% quality infer?

anonymous · Answer

it is the mass of the vapor divided by the mass of the total mixture

aaronq · Answer

hmm what equation would you use?  dS=q/T  ?

anonymous · Answer

rate equation for entropy: rate of change=+in -out+generation?? Scv=sum(mass flow in *sin)-sum(mass flow out*sout)+sum(Qcv/T)+Sgen

aaronq · Answer

hm you can assume to have 100 grams then take 20%.. as for the rest it seems that you have too many unknown entropy values

anonymous · Answer

would i need to solve the entropy equation for Q?

aaronq · Answer

yes