Question

2) A steam power plant operates on an ideal regenerative rankine cycle with superheated steam leaving the boiler, entering the turbine at 10 mPa,600C. X fraction of steam is extracted from the turbine at 0.6 mPa pressure for the high pressure open feedwater heater. Then x fraction more of steam is extracted from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater . The condenser pressure in the cycle is 5 kPa. The mass flow rate of the steam (m) circulating in the cycle is 27kg/sec. a)Draw the sketch and the corresponding t-s diagram. b)Calculate the x fraction of steam extracted from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater. c)calculate the Y fraction of steam extracted later from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater. d)Calculate qH added to the system at the boiler ha e)calculate qL extracted from the cycle at condenser f)calculate the net power output (Wn) of the power plant 8) calculate the thermal efficiency of the power plant 2) A steam power plant operates on an ideal regenerative rankine cycle with superheated steam leaving the boiler, entering the turbine at 10 mPa, 600C. X fraction of steam is extracted from the turbine at 0.6 mPa pressure for the high pressure open feedwater heater Then x fraction more of steam is extracted from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater. The condenser pressure in the cycle is 5 kPa.The mass flOw rate of the steam (m) circulating in the cycle is 27kg/sec a) Draw the sketch and the corresponding t-s diagram b)Calculate the x fraction of steam extracted from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater. c) calculate the Y fraction of steam extracted later from the turbine at 0.2 mPa pressure for the low pressure open feedwater heater d) Calculate qH added to the system at the boiler e) calculate qL extracted from the cycle at condenser f)calculate the net power output (Wn) of the power plant g)calculate the thermal efficiency of the power plant

Answer 1

80luhon! 10 M P O.6MPaX 1-X o604Peloe 2 SKPa (1-x- (x-X- Properhes at diferemt stat points dsom steam table h,htat scpa=137.25 | 0003100Y .2 ksl = ( of X103) (200-S ngT CP-P) ks1sh2 137-25 0. 2 137.9S Iy= 04.7) Ks1 0-2 M Pa S h3= htat O 2MPa 1061 X163m3 Ke = C1061x10x 600-200)) S 3-Vato2MPa 0, 192 C-Ps) 0-42Ks=102 1 Collno

=1SOS-13 504.7)ナ0.42 670 38 ks I ato-6M Pa Ps= o.6 Pa VsVEat o 6MPa- 1.10113 3) k =CI101X103)xC10,000-600 10-35 k3119 680.73 ks1ls= he 670 3810 35= アラ=)0 MPa & Tラニ6o0c at ケフ= 3625.s ksly PE 0.6MPa 2R : 28218 ks Pg= 6.2m Pa と9 ニ 6-9048-1.5303 o.9602-= X 6-5968 CO4.21710 9602)x (2201.6 2618.7 also Pro SkPa 2 S1o- S7 6.9045-0.4762 つく」o 三 11 5-015 291 76 O8119 hIO 137-75-ナ (o811×2423) 2105.9 Using emergy balance in deed oater heater xhe +Cx) h4hç Cellpa

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Answer 2

Q3: A steam power plant operates on an ideal regenerative Rankine cycle with two open feedwater heaters. Steam enters the turbine at 10 MPa and 600°C and exhausts to the condenser at 5 kPa. Steam is extracted from the turbine at 0.6 and 0.2 MPa. Water leaves both feedwater heaters as a saturated liquid. The mass flow rate of steam through the boiler is 22 kg/s. Show the cycle on a T-s diagram, and determine (a) the net power output of the power plant and (b) the thermal efficiency of the cycle.