Question 15.9: Saturated aqua–ammonia at 100 psia, 240 F, with a concentrat......

State 1 is first located using Chart 2 in Appendix E and is shown schematically in Fig. 15-29. The isotherm for 240 F has been located using a straightedge. In this case state 1 is a two-phase mixture. State 2 is located at the same point as state 1 on the diagram. The isotherm that passes through point 2 for a pressure of 30 psia is then located by trial and error and is found to be 180 F as shown in Fig. 15-29. The fraction of vapor at state 2 is given by

\frac{\dot{m}_{v}}{\dot{m}}  =  \frac{\overline{  22 f  }}{\overline{2 f 2 g}}  =  \frac{2.2  in.}{7.5  in.}  =  0.289  \frac{lbm  vapor}{lbm  mixture}

\frac{\dot{m}_{f}}{\dot{m}}  =  1   –   0.289  =  0.711  \frac{lbm  vapor}{lbm  mixture}