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Activity 4 Steam cycies ar 4. Ina thermal power plant operating on a Rankine cycie with reheat, steam at 50b and 500°C enters a high pressure turbine and leaves at 10bar. Then this steam is reheated to 500°C before it is fed to a low pressure turbine. The condenser ’ maintained at 6.05 bar. Calculate the thermal efficiency of the powe: er plant, t ‘ = mass flow rate of steam for a net power output of 20MW and the quality of steam a’ the exit of the low pressure turbine. What will be the efficiency of the power plant if the isentropic efficiency of witch turbine is 80%? ss 2. Asteam power plant operates on an ideal regenerative Rankine cycle. Steam enters the turbine at 6 MPa and 450°C and is condensed in the condenser at 20 kPa. Steam is extracted from the turbine at 0.4 MPa to heat the feedwater in an open feedwater heater. Water leaves the feedwater heater as a saturated liquid. Show the cycle on a T-s diagram, and determine (a) the net work output per kilogram of steam flowing through the boiler and (b) the thermal efficiency of the cycle. 3. A steam power plant operates on an ideal regenerative Rankine cycle. Steam enters the turbine at 60 bar and 500°C and is condensed in the condenser at 10. kPa. Steam is extracted from the turbine at 12bar to heat the feedwater in a closed feedwater heater. The steam leaves the feedwater heater as a saturated liquid. Show the cycle on a T-s diagram, and determine (a) the net work output per kilogram of steam flowing through the boiler and (b) the thermal effi iciency of the cycle. Scanned with CamScanner