Sonntag, Borgnakke and van Wylen
3.92 Find the phase, quality x if applicable and the missing property P or T. Solution: a. H2O
T = 120°C
v = 0.5 m3/kg v < vg = 0.89186
Table B.1.1 at given T:
b. H2O
sat. liq. + vap. P = Psat = 198.5 kPa, x = (v - vf)/vfg = (0.5 - 0.00106)/0.8908 = 0.56 P = 100 kPa v = 1.8 m3/kg v > vg = 1.694 sup. vap., interpolate in Table B.1.3 1.8 − 1.694 T= (150 – 99.62) + 99.62 = 121.65 °C 1.93636 − 1.694 Table B.1.2 at given P:
c. H2O
T = 263 K
v = 0.2 m3/kg
Table B.1.5 at given T = -10 °C:
v < vg = 466.757 sat. solid + vap., P = Psat = 0.26 kPa, x = (v - vi)/vig = (200 - 0.001)/466.756 = 0.4285 P C.P.
States shown are placed relative to the two-phase region, not to each other.
T
C.P. P = const.
b a a
T c
v
c
b v