Thermo Ideal Rankine Review - Multiple Choice

An ideal Rankine cycle is operating between 4MPA and 20 kPa using water as the working fluid. If 50 kg/s of steam flows through the plant, what is the pump power (rate of pump work) required by the cycle?

(Remember w_pump [kJ/kg] = v(P_2 - P_1))

• 4.05 kW

• 203 KW

• 251 kW

• 255 kW

Tags

NGSS.HS-PS3-1

An ideal Rankine cycle is operating between 4MPA and 20 kPa using water as the working fluid. What is the enthalpy of the water as it enters the boiler?

Tip: Do an energy balance on the pump:

w_pump = h_2 - h_1

• 60 kJ/kg

• 251 kJ/kg

• 255 kJ/kg

• 3906 kJ/kg

An ideal Rankine cycle is operating between 4MPA and 20 kPa with 50kg/s of water circulating as the working fluid. If steam enters the turbine at 700C, what is the quality of steam leaving the turbine?

Reminder: The entropy of the steam leaving an ideal turbine is the same entropy as the steam that comes in.

x = (Y - Y_f)/(Y_g - Y_f)

• .8962

• .8596

• .9596

• 1

Tags

NGSS.HS-PS3-4

A simple Rankine cycle is operating between 4MPA and 20 kPa with 50kg/s of water circulating as the working fluid. If steam enters the turbine at 700C, what is the work output of the turbine?

Reminder: The entropy of the steam leaving an ideal turbine is the same entropy as the steam that comes in.

w_turb = h_3 - h_4

• 39 MW

• 69 MW

• .95 MW

• 65 MW

Tags

NGSS.HS-PS3-1

A simple Rankine cycle is operating between 4MPA and 20 kPa with 50kg/s of water circulating as the working fluid. If steam leaves the turbine with an entropy of 7.87 (kJ/kg K), how much heat is rejected from the condenser?

Reminders: q_out = h_4 - h_1

x = (Y - Y_f)/(Y_g - Y_f)

• 117 MW

• 69 MW

• 203 MW

• 65 MW

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

In an Ideal Rankine Cycle, the pumping process from the condenser to the boiler is a(n):

• Isentropic Process

• Isothermal Process

• Constant Pressure Process

• Constant Volume Process

Tags

NGSS.HS-PS3-4

In an Ideal Rankine Cycle, the expansion process through a turbine is a(n):

• Isentropic Process

• Isothermal Process

• Constant Pressure Process

• Constant Volume Process

In an Ideal Rankine Cycle, the heat addition in the boiler is a(n):

• Isentropic Process

• Isothermal Process

• Constant Pressure Process

• Constant Volume Process

In an Ideal Rankine Cycle, the heat rejection in the condenser is a(n):

• Isentropic Process

• Isothermal Process

• Constant Pressure Process

• Constant Volume Process

Tags

NGSS.HS-PS3-4

Rankine Cycles use what as the working fluid?

• Fluids which undergo liquid-vapor phase change between the operating pressures

• Single phase gases through the whole cycle

• Super-critical fluids through the whole cycle

• A mixture of fluids