Question

Increasing the temperature of the heat addition (T subscript H) in any heat engine cycle, with keeping all other parameters unchanged:

A.

None of the answers.

B.

Decreases the heat added at high temperature.

C.

Increases the thermal efficiency of the cycle.

D.

Decreases the thermal efficiency of the cycle.

1 points   

QUESTION 2

The maximum thermal efficiency of the Rankine cycle power plant is achieved when:

A.

it works on Carnot heat engine cycle.

B.

the pump work is ignored.

C.

it works on Reversed Carnot cycle.

D.

the temperature of heat addition is reduced.

1 points   

QUESTION 3

Consider a simple ideal Rankine cycle with fixed boiler and condenser pressures. If the steam is superheated to a higher temperature, (select the correct statement)

A.

the moisture content at turbine exit will increase.

B.

the turbine work output will decrease.

C.

the amount of heat rejected will decrease.

D.

the amount of heat input will increase.

E.

the cycle efficiency will decrease.

1 points   

QUESTION 4

Comparing the efficiency of the real power plant cycle with the ideal Rankine cycle shows:

A.

the efficiency of the real power plant cycle is equal to the ideal Rankine cycle

B.

the efficiency of the real power plant cycle is higher than the ideal Rankine cycle

C.

the efficiency of the real power plant cycle is higher than the Carnot cycle

D.

the efficiency of the real power plant cycle is less than the ideal Rankine cycle

1 points   

QUESTION 5

A simple ideal Rankine cycle operates between boiler pressure of 3 MPa and condenser pressure of 10 kPa, with turbine inlet temperature of 600 C. If enthalpy at pump inlet is 191 kJ/kg, enthalpy at boiler inlet is 194 kJ/kg, enthalpy at turbine inlet is 3682 kJ/kg, and enthalpy at condenser inlet is 2380 kJ/kg. The mass flow rate of steam is 50 kg/s:

The thermal efficiency of the cycle is:

A.

137.2 %

B.

37.2 %

C.

37.2 MW

D.

15 %

1 points   

QUESTION 6

A simple ideal Rankine cycle operates between boiler pressure of 3 MPa and condenser pressure of 10 kPa, with turbine inlet temperature of 600 C. If enthalpy at pump inlet is 191 kJ/kg, enthalpy at boiler inlet is 194 kJ/kg, enthalpy at turbine inlet is 3682 kJ/kg, and enthalpy at condenser inlet is 2380 kJ/kg. The mass flow rate of steam is 50 kg/s:

The rate of heat removed from the condenser (in kW) is:

A.

150 kW

B.

174400 kW

C.

65100 kW

D.

109450 kW

1 points   

QUESTION 7

If the same cycle used for Refrigerator is used as a heat pump, then:

A.

the COP of the heat pump becomes higher than the COP of the refrigerator.

B.

the COP of the heat pump becomes less than the COP of the refrigerator.

C.

No relation between COP of heat pump and COP for the refrigerator.

D.

the COP of the heat pump becomes equal to the COP of the refrigerator.

1 points   

QUESTION 8

A simple ideal Rankine cycle operates between boiler pressure of 3 MPa and condenser pressure of 10 kPa, with turbine inlet temperature of 600 C. If enthalpy at pump inlet is 191 kJ/kg, enthalpy at boiler inlet is 194 kJ/kg, enthalpy at turbine inlet is 3682 kJ/kg, and enthalpy at condenser inlet is 2380 kJ/kg. The mass flow rate of steam is 50 kg/s:

The power input to the pump (in kW) is:

A.

150 MW

B.

150 kW

C.

1500 kW

D.

150 kJ/kg

1 points   

QUESTION 9

A simple ideal Rankine cycle operates between boiler pressure of 3 MPa and condenser pressure of 10 kPa, with turbine inlet temperature of 600 C. If enthalpy at pump inlet is 191 kJ/kg, enthalpy at boiler inlet is 194 kJ/kg, enthalpy at turbine inlet is 3682 kJ/kg, and enthalpy at condenser inlet is 2380 kJ/kg. The mass flow rate of steam is 50 kg/s:

The power output from the turbine (in kW) is:

A.

65100 kW

B.

150 kW

C.

109450 kW

D.

174400 kW

1 points   

QUESTION 10

A simple ideal Rankine cycle operates between boiler pressure of 3 MPa and condenser pressure of 10 kPa, with turbine inlet temperature of 600 C. If enthalpy at pump inlet is 191 kJ/kg, enthalpy at boiler inlet is 194 kJ/kg, enthalpy at turbine inlet is 3682 kJ/kg, and enthalpy at condenser inlet is 2380 kJ/kg. The mass flow rate of steam is 50 kg/s:

The rate of heat added in the boiler (in kW) is:

A.

150 kW

B.

65100 kW

C.

174400 kW

D.

109450 kW

Answer 1