TABLE OF CONTENTS (1) Determine from the Mollier diagram for steam: (a) the enthalpy of 100 pisa (689.5 kPa) saturated steam; (b) the enthalpy of 10 psia (68.9 kPa) steam containing 40% moisture; (c) the enthalpy of 100 psia (689.5 kPa) steam at 600 F (315.6 C). (2) Determine from the steam tables: (d) the enthalpy, specific volume, and entropy of steam at 145.3 psig (1001.8 kPag); (b) the enthalpy and specific volume of superheated steam at 1100 psia (7584.2 kPa) and 600 F (315.6 C); (c) the enthalpy and specific volume of high-pressure steam at 7500 psia (51,710.7 kPa) and 1200 F (648.9 C); (d) the enthalpy, specific volume, and entropy of 10-psia (68.9-kPa) steam containing 40% moisture.
1. Use the pressure and saturation (or moisture) lines to find enthalpy
Enter the Mollier diagram by finding the 100-psia (689.5-kPa) pressure line (Fig. 19.1). In the Mollier diagram for steam, the pressure lines slope upward to the right from the lower left-hand corner. For saturated steam, the enthalpy is read at the intersection of the pressure line with the saturation curve cef (Fig. 19.1).
Thus, project along the 100-psia (689.5-kPa) pressure curve until it intersects the saturation curve, point g. From here project horizontally to the left-hand scale and read the enthalpy of 100-psia (689.5-kPa) saturated steam as 1187 Btu/lb (2761.0 kJ/kg). (The Mollier diagram in Fig. 19.1 has...
