A boiler feed pump delivers 100 ft3/min of water at 400 F, 3000 lbf/in.2. What is the mass flowrate (lbm/*)? What would be the percent error if the properties of saturated liquid at 400 F were used in the calculation? What if the properties of saturated liquid at 3000 lbf/in.2 were used?
v = 0.0183 ft3/lbm (interpolate 2000-8000 psia)
m = V/v = 100 60 × 0.018334 = 91.07 lbm/*
vf (400 F) = 0.01864 ⇒ m = 89.41 lbm/* error 1.8%
vf (3000 lbf/in2) = 0.03475 ft3/lbm
⇒ m = 47.96 lbm/* error 47%
