Corrected December, 2011
4.59 Refrigerant 134a enters an air conditioner compressor at 4 bar, 20C, and is
compressed at steady state to 12 bar, 80C. The volumetric flow rate of the refrigerant
entering is 4 m3/min. The power input to the compressor is 60
Corrected October, 2011
The analysis on a mass basis of an ideal gas mixture at 50oF, 25 lbf/in.2 is 60% CO2, 25%
SO2, and 15% N2. Determine
(a) the analysis in terms of mole fractions.
(b) the apparent molecular weight of the mixture.
10.7 Plot each of the quantities in Problem 10.6 versus evaporator temperature for evaporator
pressures ranging from 0.6 to 4 bar, while the condenser pressure remains fixed at 8 bar.
p1 = 2 / bar
p2 = 8 / bar
p3 = p2
mdot = 7 / kg/min
h1 = hsat
8.11 Plot each of the quantities calculated in Problem 8.10 versus condenser pressure ranging
from 0.3 lbf/in.2 to 14.7 lbf/in.2 Maintain constant net power output. Discuss.
KNOWN: Water is working fluid in an ideal Rankine cycle
Corrected July, 2011
5.79 Two kilograms of air within a piston-cylinder assembly executes a Carnot power
cycle with maximum and minimum temperatures of 750 K and 300 K, respectively. The
heat transfer to the air during the isothermal expansion is 60 kJ. A