A steam power plant design consists of an ideal Rankine cycl

A steam power plant design consists of an ideal Rankine cycle with reheat and regeneration. Steam enters Turbine 1 at P1 and T1 at the rate of m1 and exits at P2. A fraction (y\') of the steam exiting Turbine 1 is diverted to a closed feedwater heater while the remainder is reheated to T3 before entering Turbine 2. A fraction (y\'\') of the steam exiting Turbine 2 at P4 is diverted to an open feedwater heater while the remainder enters Turbine 3. The exit of Turbine 3 is fed into a condenser that operates at P5. Saturared liquid exits the condenser and is fed to Pump 1. The outlet of Pump 1 is fed into the open feedwater heater. Saturated liquid exits the open feedwater heater and is fed to Pump 2. The outlet of pump 2 is fed to the closed feedwater heater. Saturated liquid exits the low pressure output of the closed feedwater heater and is fed through a steam trap to the open feedwater heater. Both exits of the closed feedwater heater are at the same temperature. All turbines and pumps are isentropic.

--Given Values--
m1 (kg/s) = 50
P1 (Bar) = 160
T1 (^oC) = 520
P2 (Bar) = 15
T3 (C) = 600
P4 (Bar) = 1.5
P5 (Bar) = 0.1

a) Determine the specific enthalpy (kJ/kg) at the inlet of turbine 1 inlet.
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b) Determine the specific entropy (kJ/kg-K) at the inlet of turbine 1 inlet.
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c) Determine the specific enthalpy (kJ/kg) at the exit of turbine 1.
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d) Determine the specific enthalpy (kJ/kg) at the inlet of turbine 2 .
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e) Determine the specific entropy (kJ/kg-K) at the inlet of turbine 2.
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f) Determine the specific enthalpy (kJ/kg) at the exit of turbine 2.
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g) Determine the specific enthalpy (kJ/kg) at the exit of turbine 3.
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h) Determine the specific enthalpy (kJ/kg) at the condenser exit.
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i) Determine the specific enthalpy (kJ/kg) at the exit of the low pressure pump.
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j) Determine the specific enthalpy (kJ/kg) at the exit of the open feedwater heater.
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k) Determine the specific enthalpy (kJ/kg) at the exit of the high pressure pump.
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l) Determine the specific enthalpy (kJ/kg) at the low pressure exit of the closed feedwater heater.
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m) Determine the specific enthalpy (kJ/kg) at the exit of the steam trap.
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n) Determine the specific enthalpy (kJ/kg) at the inlet to the boiler.
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o) Determine the fraction of flow (y\') diverted to the closed feedwater heater.
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p) Determine the power (MW) produced by turbine 1.
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q) Determine the power (MW) produced by turbine 2.
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r) Determine the fraction of flow (y\'\') diverted to the open feedwater heater.
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s) Determine the power (MW) produced by turbine 3.
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t) Determine the power (kW) required (a positive number) by the low pressure pump.
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u) Determine the power (kW) required (a positive number) by the high pressure pump.
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v) Determine the total rate of heat transfer (MW) supplied to the boiler.
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w) Determine the thermal efficiency (%) of the power plant.
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Solution

a) find the value of the specific enthalpy of superheated steam at the turbine 1 inlet from the steam tables.

At temperture of 520 (^oC) and a pressure of 160 bar, the specific enthalpy is 3355.6 kJ/kg

b) find the specific entropy of superheated steam at the turbine1 inlet from the steam tables.

At temperture of 520 (^oC) and a pressure of 160 bar, the specific entropy is 6.3736 kJ/kg-K

c) find the specific enthalpy of saturated steam at the turbine 1 exit from the steam tables.

At a pressure of 15 bar and saturated temperature, the specific enthalpy of steam is 2792.01 kJ/kg

d) Find the specific enthalpy at the inlet of turbine 2 from steam tables.

At a pressure of 15 bar and temperature of 600 K, the specific enthalpy of steam is 3694 kJ/kg

e) Find the specific entropy at the inlet of turbine 2 from steam tables.

At a pressure of 15 bar and temperature of 600 K, the specific entropy of steam is 7.9395 kJ/kg-K

f) Find the specific enthalpy at the exit of turbine 2 from steam tables.

At a pressure of 1.5 bar and at saturated temperature, the specific enthalpy is 2693.6 kJ/kg