Example $2\mathrm{.}14$ Vapor$-$Compression Refrigeration

A vapor$-$compression chiller system is used to cool the air stream in a room air conditioning system with total cooling load of $10-$kW as shown in the figure below. The room air stream enters the evaporator at temperature of $\backslash (\backslash$boldsymbol$\{$T$\}\_\{\backslash$mathrm$\{$ro$\}\}=26\{\}^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ and cooled to a temperature of $\backslash ($ T$\_\{\backslash$mathrm$\{$ri$\}\}=12\{\}^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash ).$ The condenser is air$-$cooled with design outdoor temperature of $\backslash ($ T$\_\{\backslash$mathrm$\{$a$\}\}=35^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ and compressor is assumed to have an efficiency of $\backslash (\backslash$eta$\_\{\backslash$mathrm$\{$c$\}\}=\backslash )85\backslash \%.$ Perform first law analysis of the refrigeration system assuming R$-134$ as the refrigerant and determine: $($a$)$ mass flow rate of the refrigerant, $($b$)$ COP of the system, and summarize the ratings of all major components of the vapor compression refrigeration system.

Figure $2\mathrm{.}32$ Vapor compression refrigeration system with air$-$cooled and water$-$cooled condensers for heat rejection: $($a$)$ vapor compression refrigeration with air$-$cooled condenser and $($b$)$ vapor compression refrigeration with water cooled condenser.