Calculating the Coefficient of Performance of an Automobile Air Conditioner
An automobile air conditioner uses a vapor-compression refrigeration cycle with the environmentally friendly refrigerant HFC-134a as the working fluid. The following data are available for this cycle.
\begin{array}{clc}\hline \text { Point } & \text { Fluid State } & \text { Temperature } \\\hline 1 & \text { Saturated liquid } & 55^{\circ} C \\2 & \text { Vapor-liquid mixture } & \\3 & \text { Saturated vapor } & 5^{\circ} C \\4 & \text { Superheated vapor } & \\\hline\end{array}a. Supply the missing temperatures and the pressures in the table.
b. Evaluate the coefficient of performance for the refrigeration cycle described in this problem.