HW - 34 (See HW-33) A Rankine cycle with regeneration and reheat using water as the...

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HW - 34 (See HW-33) A Rankine cycle with regeneration and reheat using water as the working fluid and operating steadily is shown below. Steam enters the adiabatic high-pressure turbine (HPT) at 100 bar and 440C (State 1) and expands to 7 bar (State 2) with an isentropic efficiency of 85%. A fraction of the steam is extracted at State 2 and the remaining steam is reheated to 7 bar and 440C (State 3) before entering the adiabatic low- pressure turbine (LPT) and expands to 0.06 bar (State 4) with an isentropic efficiency of 85%. Saturated liquid water at 0.06 bar exits the condenser (State 5) and enters an adiabatic low-pressure pump (LPP) which increases the liquid water pressure to 7 bar (State 6) with an isentropic efficiency of 100%. Liquid water leaving the LPP (State 6) is mixed with the extracted steam (State 2) in a rigid, well-insulated mixing chamber. The mixed stream exits the mixing chamber as saturated liquid at 7 bar (State 7), enters an adiabatic high-pressure pump (HPP) which increases the pressure to 100 bar (State 8) with an isentropic efficiency of 100%. Liquid leaving the HPP is supplied back to the boiler. Remaining Steam = (1-y)mst steam Boiler 1 m Steam HPT LPT 2 3 4 Extracted Steam yms steam Mixing HPP 8 7 Chamber LPP 6 5 Condenser (a) Calculate the net specific work for the cycle using the specific work (per unit mass flow rate leaving the boiler) for HPT, LPT, LPP, and HPP, in kJ/kg. (b) Determine the thermal efficiency of the cycle, in %. (c) Compare the value calculated in HW-34(b) with that calculated in HW-33(c). Is it higher or lower? Explain. HW - 34 (See HW-33) A Rankine cycle with regeneration and reheat using water as the working fluid and operating steadily is shown below. Steam enters the adiabatic high-pressure turbine (HPT) at 100 bar and 440C (State 1) and expands to 7 bar (State 2) with an isentropic efficiency of 85%. A fraction of the steam is extracted at State 2 and the remaining steam is reheated to 7 bar and 440C (State 3) before entering the adiabatic low- pressure turbine (LPT) and expands to 0.06 bar (State 4) with an isentropic efficiency of 85%. Saturated liquid water at 0.06 bar exits the condenser (State 5) and enters an adiabatic low-pressure pump (LPP) which increases the liquid water pressure to 7 bar (State 6) with an isentropic efficiency of 100%. Liquid water leaving the LPP (State 6) is mixed with the extracted steam (State 2) in a rigid, well-insulated mixing chamber. The mixed stream exits the mixing chamber as saturated liquid at 7 bar (State 7), enters an adiabatic high-pressure pump (HPP) which increases the pressure to 100 bar (State 8) with an isentropic efficiency of 100%. Liquid leaving the HPP is supplied back to the boiler. Remaining Steam = (1-y)mst steam Boiler 1 m Steam HPT LPT 2 3 4 Extracted Steam yms steam Mixing HPP 8 7 Chamber LPP 6 5 Condenser (a) Calculate the net specific work for the cycle using the specific work (per unit mass flow rate leaving the boiler) for HPT, LPT, LPP, and HPP, in kJ/kg. (b) Determine the thermal efficiency of the cycle, in %. (c) Compare the value calculated in HW-34(b) with that calculated in HW-33(c). Is it higher or lower? Explain.