Q$1)$

A cascade refrigeration system is designed to produce $30$ tons of reffigeration at $-40C$ with Amonia$($R$-717)$ flowing in the low stage side. The condensing temperature of the Amonia is $5C,$

R$-22$ is used in the top cycle with the evaporation at $-10C$ and the condensing temperature is $35C.$ The liquid refrigerant leaves the condenser in the upper cycle is sub$-$cooled by $10C.$

I. Draw the P$-$h diagram for each cycle.

II$.$ Find The mass flow Find The mass flow rate for the R$-717$

IV$.$ Find The total power required for the system $q,v^{}=m^{}(h_2-h_1)+m^{}(h_1-h_a)$

$=\frac{q_e}{w}=\frac{Q_e}{w}=\frac{105\mathrm{.}3}{48\mathrm{.}63}=2\mathrm{.}165$

$Co{p}_{R-22}=\frac{q_e}{H}=\frac{(h_1-h_u)}{(h_2-h_1)}=\frac{(390-210)}{(4010+770)}$

$Co{p}_{R-22}=$

$\{\begin{array}{c}\text{:}{m}^{}{m}^{}{h}_c+m^{}{h}_1=m^{}+m^{}{h}_c+m^{}{h}_b^{}\end{array}$