Saturated vapor is condensed to saturated liquid in a condenser. The heat capacity ratio is $C_r = \displaystyle{\frac{C_{\text{min}}}{C_{\text{max}}}}$. The effectiveness $(\varepsilon)$ of the condenser is
- $\displaystyle{\frac{1-\text{exp}[-NTU(1+C_r)]}{1+C_r}} \\$
- $\displaystyle{\frac{1-\text{exp}[-NTU(1-C_r)]}{1-C_r\text{exp}[-NTU(1-C_r)]}} \\$
- $\displaystyle{\frac{NTU}{1+NTU}} \\$
- $1 – \text{exp}(-NTU)$