Problem #1: (50 pts.)
Water is the working fluid in a Basic Rankine cycle which delivers 1MW of net power output. The boiler operates at 60bar and heats the water to 500°C. The turbine expands the water vapor to a pressure of 1bar and has an adiabatic efficiency of 90%. The condenser produces saturated liquid water which can be considered incompressible passing through the 85% efficient pump.
Complete the property table below and determine: 3
a) The specific net work in kJ/kg.
b) The mass flow rate in kg/s. B T
c) The heat absorption rate in the boiler in kW.
d) The Carnot efficiency of the cycle.
4
e) The thermodynamic efficiency of the cycle. 2
C
f) Sketch the processes in a T-s diagram.
P
1
1 2 3 4
Pump Inlet Boiler Inlet Turbine Inlet Condenser Inlet
P [bar]
T [°C]
X [1]
h [kJ/kg]
s [kJ/kgK]
Problem #2: (50 pts.)
The p-v diagram shows an air-standard Diesel cycle that operates on a piston-cylinder assembly with maximum (BDC) volume of 1.5L, compression ratio of 18, and cutoff ratio of 1.8. At the beginning of the isentropic compression process (1) the pressure is 100kPa and the temperature
is 27°C. Use the variable specific heat model to complete the property table below and
determine: p
2
a) The mass of air in the system in kg XXXXXXXXXX
b) The heat absorbed in the combustion process (2-3) in kJ.
c) The net work in kJ.
d) The mean effective pressure in kPa. 4
e) The Carnot efficiency of the cycle.
f) The thermodynamic efficiency of the cycle. 1
v
1 2 3 4
P [kPa]
T [K]
v [m3/kg]
u [kJ/kg]
h [kJ/kg]
Vr[[1]
Document Preview: Problem #1: (50 pts.)
Water is the working fluid in a Basic Rankine cycle which delivers 1MW of net power output. The boiler operates at 60bar and heats the water to 500°C. The turbine expands the water vapor to a pressure of 1bar and has an adiabatic efficiency of 90%. The condenser produces saturated liquid water which can be considered incompressible passing through the 85% efficient pump.
Complete the property table below and determine:3a) The specific net work in kJ/kg.b) The mass flow rate in kg/s.BTc) The heat absorption rate in the boiler in kW.d) The Carnot efficiency of the cycle.4e) The thermodynamic efficiency of the cycle.2Cf) Sketch the processes in a T-s diagram.PThis document was truncated here because it was created in the Evaluation Mode.