Question

In: Mechanical Engineering

A Rankine cycle uses water as its working fluid. The mass flow rate of water through...

A Rankine cycle uses water as its working fluid. The mass flow rate of water through the cycle is 150 kg/s. Superheated vapour exits the boiler at 8 MPa and 560 °C. The condenser pressure is 8 kPa. The water at the pump inlet is 35 °C. The isentropic efficiency of the pump is 75% and the isentropic efficiency of the turbine is 91%. The turbine and pump can be treated as adiabatic. The pressure drops of the working fluid as it follows through the boiler and through the condenser are negligible. Kinetic and potential energy effects can also be ignored. For your analysis use the state point numbering scheme indicated in the following schematic: Do the following:

I. Draw the state points on a T-s diagram. Take care to locate each point in the correct region: superheated, mixed and subcooled.

II. Calculate the power developed in by the turbine.

III. Calculate the rate of heat transfer to the steam passing through the boiler.

IV. Calculate the power consumed by the pump in MW.

V. Calculate the rate of heat transfer from the cycle to the cooling water in the condenser in MW.

VI. Calculate the cycle’s back work ratio.

BONUS: Comment on state 2, what kind of effect can this have on the turbine performance?

Solutions

Expert Solution

samet mamat answered 3 years ago
Next > < Previous

Related Solutions

An ideal Rankine Cycle with reheat uses water as the working fluid with a flow rate...
An ideal Rankine Cycle with reheat uses water as the working fluid with a flow rate of 0.15 kg/s. At the inlet of the turbine (state 1) the water is a superheated vapor at 475ºC and 11 MPa. The pressure at the exit of the first stage of the turbine is 0.9 MPa. The reheat temperature (state 3) is also  475ºC.   The condenser pressure is 8 kPa, and the water exits as a saturated liquid Find: (a) The heat addition to...
An ideal Rankine Cycle with reheat uses water as the working fluid with a flow rate...
An ideal Rankine Cycle with reheat uses water as the working fluid with a flow rate of 0.15 kg/s. At the inlet of the turbine (state 1) the water is a superheated vapor at 475ºC and 11 MPa. The pressure at the exit of the first stage of the turbine is 0.9 MPa. The reheat temperature (state 3) is also  475ºC.   The condenser pressure is 8 kPa, and the water exits as a saturated liquid Find: (a) The heat addition to...
An ideal Rankine cycle with reheat uses water as the working fluid. As shown in the...
An ideal Rankine cycle with reheat uses water as the working fluid. As shown in the figure below, the conditions at the inlet to the first turbine stage are 1600 lbf/in.2, 1200°F and the steam is reheated to a temperature of T3 = 800°F between the turbine stages at a pressure of p3 = p2 = 400 lbf/in.2 For a condenser pressure of p5 = p4 = 5 lbf/in.2, determine: (a) the quality of the steam at the second-stage turbine...
A Rankine power cycle with reheat uses water as the working fluid. The inlet conditions of...
A Rankine power cycle with reheat uses water as the working fluid. The inlet conditions of the first stage turbine are 14MPa and 600oC. All the turbines are known to have isentropic efficiency of 85%, however the pump is assumed as an isentropic pump. If the maximum temperature is kept at 600oC and the condenser pressure is 6 kPa, by constructing a suitable plot, show that having more than 2 reheat stages is not practical. (Hint: Take at least three...
A Rankine power cycle with reheat uses water as the working fluid. The inlet conditions of...
A Rankine power cycle with reheat uses water as the working fluid. The inlet conditions of the first stage turbine are 14MPa and 600C. All the turbines are known to have isentropic efficiency of 85%, however the pump is assumed as an isentropic pump. If the maximum temperature is kept at 600C and the condenser pressure is 6 kPa, by constructing a suitable plot, show that having more than 2 reheat stages is not practical. (Hint: Take at least three...
Consider a simple ideal Rankine cycle which uses water as the working fluid. The net power...
Consider a simple ideal Rankine cycle which uses water as the working fluid. The net power of power plant is 220-MW. At the turbine inlet, steam is at 9 MPa and 560°C. The condenser pressure is 20 kPa. Determine the following values.   The temperature at the pump inlet. °CThe specific enthalpy at the pump inlet. kJ/kgThe specific volume at the pump inlet. m3/kgThe pump work. kJ/kgThe temperature at pump exit. °CThe specific entropy at turbine inlet. kJ/kg·KThe quality of steam...
Consider a simple ideal Rankine cycle which uses water as the working fluid. The boiler pressure...
Consider a simple ideal Rankine cycle which uses water as the working fluid. The boiler pressure is 6100 kPa and the condenser pressure is 30 kPa. At the turbine inlet, steam is at 480°C. The isentropic efficiency of the turbine is 92 percent. The pump losses are negligible and the water leaving the condenser is subcooled by 6.3°C. The boiler is sized for a mass flow rate of 20 kg/s. Determine the following values. The temperature at the pump inlet....
Problem 2. Problem 1. An ideal Rankine Cycle with reheat uses water as the working fluid...
Problem 2. Problem 1. An ideal Rankine Cycle with reheat uses water as the working fluid with a flow rate of 0.15 kg/s. At the inlet of the turbine (state 1) the water is a superheated vapor at 475ºC and 11 MPa. The pressure at the exit of the first stage of the turbine is 0.9 MPa. The reheat temperature (state 3) is also  475ºC.   The condenser pressure is 8 kPa, and the water exits as a saturated liquid Find: (a)...
3.A simple Rankine cycle uses water as the working fluid. The boiler operates at 6000 kPa...
3.A simple Rankine cycle uses water as the working fluid. The boiler operates at 6000 kPa and the condenser at 50 kPa. At the entrance to the turbine, the temperature is 450°C. The isentropic efficiency of the turbine is 90 percent, pressure and pump losses are negligible, and the water leaving the condenser is subcooled by 6.3°C. The boiler is sized for a mass flow rate of 20 kg/s. Determine (a) the rate at which heat is added in the...
Water is the working fluid in an ideal Rankine cycle. Saturated vapor enters the turbine at...
Water is the working fluid in an ideal Rankine cycle. Saturated vapor enters the turbine at 16 MPa, and the condenser pressure is 8 kPa. The mass flow rate of steam entering the turbine is 50 kg/s. Determine: (a) the net power developed, in kW. (b) the rate of heat transfer to the steam passing through the boiler, in kW. (c) the percent thermal efficiency. (d) the mass flow rate of condenser cooling water, in kg/s, if the cooling water...
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT