Question 6.227E: A 1 gallon jug of milk at 75 F is placed in your refrigerato...

C.V. Jug of milk. Control mass at constant pressure.
Continuity Eq.:              m _{2}= m _{1}= m;

Energy Eq.3.5:              m \left( u _{2}- u _{1}\right)={ }_{1} Q _{2}-{ }_{1} W _{2}

Entropy Eq.6.37:          m \left( s _{2}- s _{1}\right)=\int d Q / T +{ }_{1} S _{2  gen}

State 1:   Table F.7.1:        v _{1} \cong v _{ f }=0.01606   ft ^{3} / Ibm ,          h _{1}= h _{ f }=43.085   Btu / lbm ;

State 2: Table F.7.1:        h _{2}= h _{ f }=8.01   Btu / lbm , s _{2}= s _{ f }=0.0162   Btu / lbm  R

Process:        P = constant = 14.7 psia      \Rightarrow{ }_{1} W _{2}= mP \left( v _{2}- v _{1}\right)

Substitute the work into the energy equation and solve for the heat transfer

The entropy equation gives the generation as

…………………………………..

Eq.6.37 : S_{2}-S_{1}=\int_{1}^{2} d S=\int_{1}^{2} \frac{\delta Q}{T}+{ }_{1} S_{2 gen}

Eq.3.5: E_{2}-E_{1}={ }_{1} Q_{2}-{ }_{1} W_{2}