© 30 Ge) 10:31 Steam Power Plant (... | PRIME REVIEW ONLINE "MECHANICAL ENGINEERING REVIEW 1 ‘The urine work and the pump wrk in a Rankine cycle are 1200 ‘ecg and 20 ki/kg respectively. What isthe efficiency ofthe yc if the heat generated by the generator is 3000 ki/kg ? A. 36.77% ©, 3545 % B. 39.33% D, 38.32% Solan Noet NOW, . 1200 =20 _ 3935 QQ 3000 = 39.30% Calculte the enthalpy of water at 212°F and 14.7 psi considering the dryness factor is 30%. ‘A. S41 Bulb C354 Bub B. 471 Biwlb D. 410 Brw/b Slaten Use the approximate enthalpy formula of Tiquid. hy=CpAT = 1.0 BtwlbR 212-32) R (212~32) = 180 Btu/b hg = 970 Buu b= he + xhy = 180 + 0.3(970) = 471 Bru Fans 3. What isthe average fuel discharge line othe boiler? ‘A. 180 200°F B.240-260°F C160 180° D. 140 160°F Answer: A mperature range ofthe din the 4. A thermal powerplant generates 4000 kW and 400 kW for suxiliaries. Determine the net dermal efficiency if the heat generated by fel is 15000 kW. As ©. 28% B 26% D. 30% Selon Wa W-Wa, _ 4000 = 400 @ 150) 24-24% 5. Whats the highest pressure under which distinguishable liquid and ‘vapor phases can exist in equilibrium? A. Maximum pressure B. Atmosphere Critical pressure D. Peak pressure Answer: € 6. Ima Rankine cycle, steam enters the turbine at 25 MPa and condenser of 50 kPa. What isthe thermal efficiency of the eycle? Steam Properties: 4125 Mpa 2808.1 Lie, S, = 62575 AK 029 Lrg, Ski. 010300 nA A.2855.% ©.3012% B.2887% D.3L79% Slatin ‘@RBUs CFL GT DG COR BEL NOSAMD&ONGUERA TS CEBUGIY TEL WO 0260175, a ‘RIME REVIEW ONLINE 8 al atmosperie pressure, ealculate the the heat ‘temperature of water from 30°C wo 100°C ©. 1,392.34 Kikg 1D. 540.45 Kirke F Bia antl ‘hy = cpt = 4.187(100) = 418.7 Kikg At LO0C: dug = 2257 Ki/kg 13. A converging ~ diverging nozzle isthe standard equipment in __ POWER & INDUSTRIAL PLANT ENGINEERING RIMES SUPPLEMENTARY ENHANCERS STEAN POWERPLANT We NM e Atpoine (= 2803.18 /A3 62575 Wk K ‘At poi (2): 8, = 6.2575 KI/kg-K Use: Caleadator to find ‘Moe 32 x) | v0) 10910] 34049 g109104]340.49+ 23054 oso | =26158 5939] = 62575) =2172.11 kifkg Pra: by=h, = 340.49 Kky Pa: beh sw, where: W, = ¥(P)-P,) cosn0 (800-0) eR0 235 Kk Solving for hy = 2803.1-2172.11 = 6309 AY Ag Solving for, i 2b, + W, = 34049 625235 = 348.0135 4 / A then: Q.=h,~h, =2803.1-343.0135 = 2460.0910/kp 0.99 ~ 25035, 6000 12585 = 25.55% ‘A supesteit steam Rankine cycle has turbine inlet conditions of 175, MPa and 530°C expands ina turbine to 0.007 MPa. The turbine and pump polytropic efficiencies are 0.9 and 0.7 respectively. Pressure losses between pump and furbine inlet are 1.5 MPa, What should be the pump work ia kU/ke? A273 ike B 2987 ike Slosn © R47KIne 1D. 3325 KImy. Solving for W, va wn seam Near So: We (0010075 sn'/ks = {aoo100s2 Jon 5+1.5)-0.007 ] a (1000 kPa/MPa) Flows through the nozzles and diffuses with increasing fui velocity ‘will create an equivalent ‘decrease in the static enthalpy of uid increase inthe static enthalpy of uid ‘decrease in the intemal energy of fluid ‘decrease inthe dynamic enthalpy of fluid pose Answer: A. POWER & INDUSTRIAL PLANT ENGINEERING ‘PRIMES SUPPLEMENTARY ENHANCERS STEAM POWER PLANT ) “A. subsonic airraft B areal[MECHANICAL ENGINEERING REVIEW 9, Considering normal atmosperic pressure, calculate the the heat needed to raise the temperature of water from 30°C to 100°C ‘with 60% quality, A. 957.38 k/ks ©. 1,392.34 ike B. 1,647.29 kik, D. 540.45 ki/kg 4.187(100) = 418.7 Kirke At 100°C: 1257 KVkg by + hy = 418.7 + 0.60(2257) = 1,772.9 Kitkg. 1(4.187)(100-30) + 1(1772.9 - 418.7) = 1,637.29 Kiikg (an) 10,__Dry saturated steam at 55 bar (0.55 MPa) is expanded isentropically (0 (0.2 bar, find the dryness fraction of the steam st the end of the expansion, Steam Properties: AUS.5 har (0.55 MPa) Se= 6.790 kithg 10.20 bar (0.020 MPa) $= 08322 kg k Su = 20075 Wg.K ©. 84.22% D. 454% A 458% B. 87.58% Seton By: Calculator Mode 32 x(s)_ | quality) fos] 1 #7075 4100 0832 ‘Steam enters the superbeater ofa boiler at a pressure of 25 bar and “dryness of 0198 and leaves atthe sane pressure ta lemperstre of 370°C. Calculate the heat energy supplied perky of steam supplied in the supeshoate. © 30 Gs) 10:32 a POWER & INDUSTRIAL PLANT ENGINEERING RIMS SUPPLEMENTARY ENHANCERS STEAM POWER PLANT ((W,-,) = 6 g/s (1000 1504/48) 100 kW = 5.1 MW A converging ~ diverging nozzle isthe stasard equipment i AA subsonic sieraft B. supersonic aircraft C. hypersonic sirerat D. tisonicairratt Answer: B ‘A back pressure steam turbine of 100,000 kW serves as a prime mover ina cogeneration system, The boiler admis the return water ata temperature of 66°C and produces the steam at 6.5 MPa and 455°C. ‘Steam then enters aback pressure turbine and expands to the pressure ‘of the process, which is 0.52 MPa. Assuming a boiler efficiency of 80% and neglecting the effect of pumping andthe pressure drops at various location, what isthe incremental heat rate for electric? ‘The following enthalpies have been found, turbine entrance = 3306.8 kl kg, exit = 2700.8 ki/kg; boiler entrance 276.23 kiikg, exit= 3306.8 Kikg. A. 22504231hg B. 5224432 ig Sete ©. 1243572 wag D, 2223482 ike Solving for W, v= HES HOHE) 6 ry = 2250823 by/kW-be Steam Properties: 18125 bar and 370°C = SITAR 15. An increase in stagnation presse wil increase the mas Mux through A125 bar the fy = 962.11 Lig, hy = 1840.0 kt 1A diverging nozzle B. converging orzle AWWSSIRIke ——C. ISKISBUg . converging - diverging nozsle BSO415Whg DD. 245.25KNg D. none ofthese Soo Answer: B Pit (1); Soin fr (by: Castor) Mode 32 16, Find the specific entropy of wet team of temperature 195°C and x(dones) ’ Sees 090 = to sea. ‘Steam Properties 1 (soar stsa Arnos: ‘$= 2.284 Lite, 185 Uke AOS Mig C. 5268 Uke K B 70s uAgK D. 3575 ig K ‘io Mod 32 x (Quay y (cauopy) ro 284 21 [22m sans=6309 12, Aturbine in a Rankine cycle has an available enthalpy of 1000 Ki $=099=6,0505 yf Determine the net ele ouput ifthe mass flow ates 6 kgs andthe * mp works 150 kg. hos MW cc. 46Mw B37 MW D.sIMW Sdn Y ME REVIEW ONLINE POWER & INDUSTRIAL PLANT ENGINEERING ‘AL ENGINEERING REVIEW ‘PRIME’ SUPPLEMENTARY ENHANCERS (STEAM POWER PLANT] 1 © mhie have he sume valu of stagnation enhay A 9124 alled___ B 10210 D®© 30 Gs) 10:32 PRIME REVIEW | nel 17. Is the locus of states which have the same value of stagnation enthalpy and mass flux are called A. Fanno Line BL Straight Line © Willan’s Line D. Cross Cut Line Answer: A 18, Steam expands adiabatically in turbine from 2000 kPa, 400°C kPa, 250°C. What isthe effectiveness of the process in percent assuming an atmospheric temperature of 15°C. Neglect changes in kinetic and potential energy Steam Properties ‘At 2000 kPa and 400°C At 400 kPa and 250°C 400 ha S76 4dAg 20642 ihe SS 71271 RAE $= 789 LAG A. 196% ©. $245 % B 842% D.1AS7% Sten a. 0-0, BTS 2247.6 ~ 29642 (Gears 2964.2)—(15+273)(7.271- 73789) =079625 = 79.628% Casa) 19. Combination of mass and momentum equations into a sinale equation and plotted in hs plane yield acurve called A. Fair Line B. Froh Line ©. Cutting Line D. Rayleigh Line Answer: D 20. nan open feedwater heater fora seam powerplant, saturated steam at “Tharis mixed with subcooled liquid at 7 bar and 25°C, Just enough steam is supplied to ensure thatthe mixed steam Jeaving the heater ‘will be saturated liquid at 7 bar when heater efficiency is 90%, Calculate the mass low rate of subcooled liquid ifsteam flow rate is (0.865 kg per second, Steam properties: AT ar sanratedvopor At 7 ba, sauated Nui, hex 27035KIRg Wy = 69722 Lig 1 har, and 25°C: hy = 1055 Ug A278 ©. 2286 B. 3.356 D. 3948, Selon * (aMes kg/sy(2768 5 697.22) 27185 kg/s 21. A steam plant operates with an intial pressure of 1.70 MPa and 370°C temperature and exhaust heating system at 0.17 MPa. The ‘condensate from the heating system is returned tothe boiler at 65.5°C land the heating system ulizes from is intended purpose 90% of the fenergy transfered frm the stam it receives, The turbine efficiency i 70%. If the boiler efficiency is 80%, what is the cogencratn cificiency ofthe system in percent. Neglect pump work ‘Steam properties: AU L.7 MPa, and 370°C hh = 3187.1 kiag ALL? Mpa POWER & INDUSTRIAL PLANT ENGINEERING A 8 ©9128 B. 10210 D.@ Selaton Wty a othapies: bh, = S187 BU/kg. =5, = 7.1081 Ai/kg K Solving fori, Made 32 x) yh) suas | 48320 21aisze |4s3.2042216 57062= 7.1814] =26992 7.10815 =2670.73 if 2.14 Wg 61499 K/h s7.1-267073)(07) Qe= (heh) use) 2670.73-274.14)(09)=2156931 bg h-b,) 1 3612 Ki/ks OF 1.4594215631 ‘36ai2 22. A coal-fired power plan has turbine-generator rated at 1000 MW ‘oss. The plant required about 9% of this power for its internal ‘operations. Ituses 9800 tons (1 ton = 907 kg) of coal per day. The coal hhasa eating value of 6:388.9 kCaVkg, and the steam generator cffciency is 86%. What ts the net station efficiency ofthe plant in percent? Note: (1 ton = 907 kg) = 0.6916 = 69.16% A 307% ©. 674% B. 4001% D, 30.12% Selten Ne Output sme Net Input where: ‘Net Quit = Raed (12% seg) and Net Inpat = m,Q,, i. one) CC Ty (24 ay (30/4) anaes “03307 = 33.07% faite 23. Compute the heat rejected from a cylinder containing steam at 2 Mpa and 250°C if itis rigid and is cooled until the quality is 30%. Given the following AL2 Mpa and 250°C: w ‘At2 Mpa, (saturated) 1 = 000011767 mig, 09863 mg, 011144 mig 26796 Kihg 80644. uy. = 1693.8 A 3M Sky ©. -8974 Wks 265.02 Kikg D, -1452.34 Kikg 906.44 + 0.3(16938) = 1414.58 ke (U414.88 - 2679.6) = -1,265.02 Kg 7.1081 bis Wy= 27414 bIhy "em rn ir DG Com DEL ROGANDAONQUEASTE CEBU TEL NO O16 8175 MAMMAL HLS CFBLDG CORR PAPAS LOYOLA STS SAVPALC MANILA TEL NO 91590 & PRIME REVIEW ONLINE POWER & INDUSTRIAL PLANT ENGINEERING “AMICAL ENGINEERING REVIEW T ~ PRIMES SUPPLEMENTARY ENHANCERS STEAM POWER PLANT | © U7bae (0.7 Mpa) and 0.95 dey is expanded to 9 $ '5 MPa. Calculate the dryness fraction of the ‘ac expansion flows the law PV = C. sta) At4.Sbar( 045 MPa) cnce7IB nig Vz = 04139 mi A 0974 ©. 0765 B O86 D. 0667 Selaens 27. A.23.5kg of steam per second at $ MPa and 400°C is produced by a ‘steam generator. The feedwater enters the economizer at 145°C and eaves at 205°C, The steam Jeaves the boiler drum with a quality of ein cones 3h el peal ee hhaving a heating value of 25,102 ki/kg. What would be the over-all fine of even esaPRIME REVIEW ONLINE [MECHANICAL ENGINEERING REVIEW 24. 0.2 of steam at 7 bar (0.7 Mpa ) and 0.95 dey is expanded 10a pressure of (4.5) 0.45 MPa. Calculate the dryness fraction ofthe ‘expanded steam ifthe expansion follows the law PV = C. Steam Properties: AUT bar( 07 MPa) At4.5 bar (0.45 MPa ) Vj=02728mikg Vy=0-4139 mig A. ost ©. 0765, Bose D. 0667 Seton Solving forthe mass of steam wed — Solving for V, RV=RN, (00 pa}(02m)=(045)y, ¥,= 031m atin’ Drypess Fraction — inv,” (072g) (08139007) = 0974 974% 25. An inventor proposes to develop clectical power by withdrawing heat from the geyser fields of northern California and converting ital to ‘work in power turbines. This scheme will not work because ‘A. the geyser fields have only limited lifetime BB the salimty ofthe steam is too great it violates the first law of thermodynamies 1D. it Violates the second law of thermodynamic Answer: D 26, A boiler operates at 1.24 MPa abs and delivers dry and Saturated steam, ‘which is expanded to 100 kPa atmospheric pressure ina steam engine hhaving a steam rule of 12 ky per horsepower. Temperature of eedwater is 93°C. Find the Rankine vapor e¥ele efficiency. Steam properties: ‘he @ 124MPa = 2786 kinky S:@ 124MPa = 65119 kg @010MPa 457 = 1.3026 LIke K. sy = 6.0568 Lag hy = 41746 kbhe, yg = 2258 ag Wy = 00010432 mine A. 18% c.24% B19% D.32% Selon Enthalpies and extopis: by, = 2786 bi/kg, Solving for, Mode 32 x() | v(h) 11.3006 | 417.46 130264] 417.46+ 6.0868 7.3504 65119 Wfke-K thes, y= 5, $= 65119) = 255051 big y= Baga ATA Kg Solving for W, W, = 9 (AP) = 0.0010152 m’/Ag (1240400 APa) 1.189 Khe thas, h-h-W, i= hw, gn 2786 = 2389. 76 — 417.46 419. -17968 = 17 968% © 30 Gs) 10:33 a POWER & INDUSTRIAL PLANT ENGINEERING ~PRIME'S SUPPLEMENTARY ENHANCERS STEAM POWER PLANT 27. A285 kg of steam per second at § MPa and 400°C is preduced by a steam generator. The feedwater enters the economizer at 145°C and leaves at 205°C. The steam leaves the boiler drum witha quality of ‘98%. The unit consumes 275 kg of coal per second as received hhaving a heating value of 25,102 ki/kg. What would be the over-all efficiency ofthe unit in percent? Steam properties ALSMPaandd00%C: ——A1205 75.04 kg ASC A 6s 88 B. 9s D7 Slaten 28. Ina condensing steam engine A. condensed seam is supplied 'B, steam condenses inside cylinder steam condenses as soon a it leaves the eylinder 'D, exhatist steam is condensed ina condenser Answer: D 29. A closed system consisting of | kg of superheated steam at 20 bar (2 MPs) and 400°C is cooled at constant volume until the pressure is 12 thr (12 Mpa). Pd in confon of the seam tthe tower presse Sam Properties 120 bar 2a 400°C hh = S208 Lg 1 201511 mis O16%2 a ag A 04058 €. 07258 Bosse Deoass sale « J asnim fg Dapeng aye 01st mfg 3)" oes fig = 09259 30.) Steam enters throttling calorimeter ata pressure af 1.03 MPa, The calorimeter downstream pressure and temperature ae respectively (0.100 Mpa an 125°C. What is the percentage moisture ofthe supply Properties of Steam: Ps (Mpa) ng (kd7g) he (hdrke) 1.03 2010.7 277928 Note: At 0.100 MPa and 125°C, h= 2726.6 kite A262 caus Bs2t D198 Slaten (0) |y(oists) £21724 100 20107 a10035} sama} moisture = 2726.67 = 2.6185% e ~ \EREVIEW ONLINE POWER & INDUSTRIAL PLANT ENGINEERING CAL ENGINEERING REVIEW 'PRIME'S SUPPLEMENTARY ENHANCERS ( STEAM POWER PLANT ) a © eee eee Sdoson of converging - diverging nozzle under supersonic flow ats, ereating_. Qy smh = (15kg/s)(2200 ~ 350081/R5) C. shock wave ‘D. none of these A sound wave B. tidal wave Answer: ©Ste _ PRIME REVIEW [MECHANICAL ENGINEERING REVIEW © 30 Gs) 10:33 a Elm a LL POWER & INDUSTRIAL PLANT ENGINEERING PRIME’S SUPPLEMENTARY ENMANCERS.( STEAM POWER PLANT ONLINE 31. Forback pressure valves, abrupt changes in uid properties occur ina Seton ‘ery thin section of converging - diverging norele under superionic Moss conditions, creating (Q, =m = (15ka/s)(3200 ~ 350044/ha) A. sound wave C. shock wave EW B. tial weve Di none a these Limi 37. Generally steam turbines in power station operate at ‘5 300 rpm 1000 rm 32, ImaRankine cycle, saturated tigi water a 1 bars compressed B 4000 pm D.S75 mpm ‘sentopically to 150 bar. Fiat by beating ina bor and then by ‘superheating at constant pressure of 150 bar, the water substance is —s ‘ought o 750 K. Aer aia reversible expansion ina turbine (01 . ‘bar, it is then cooled in a condenser to a saturated liquid. Hew much 38. In an experiment to determine the dryness fraction of steam. a sample re uataseu? at presse of 1.1 ar (0.11 MPa was blown into a vessel Sooet. peri containing 10 kg of water a 15°C. The final mass of water inthe A 1S) bok MEMPaj ad 2900 (427%C) ‘essel was 10.75 ke and the final temperature 55°C. Find the dryness Fens tik 5) C0259 Ling acon of seamaking the wat equiva of he esl a 0.5, team Properties Ae Ther fittihibe Steam at 11 bar (0.11 MPa } y= 417.46 kifkg, Sj = 1.3026 kilvkg. K 429g ‘Ingg = 2258 kiMkg, Sip = 6.0568 kirkg. K 2251 kitke Water Propenis A 9s191IKg——C. TH69KIRG Water a 55°C Waters 15°C B 9769kne iD. 769.91SAg h = 2M02kUAgh = 629KIKg Sen A ogi ©. 09136 Enthalpies & Entropies: B. 0.8945 D. 0.8797 HOS bi/kg. = 62549 bi/Ag See Solving for Cau (Mode 3 2) a Gin x) |») wheres =mbasdh=h, + 5h, £13026 | 41746 Soi glamss| 4746+ mb, mb, oth ni (10.25~10)[429 + a(2251)}+ (10+ 0.45 )(62.9) - 10.75 +045)(7302) 2263.7 kg aad sn ~ 2283 39, Which of the following shows ie relationship ofthe steam 38. Thedifference in enhapy tthe entrance and exit in the fi wn consumption andthe load of steam turbine -generator? second stage ofa reheat power plant ae 500 kirk and 900 Kk i respectively. Determine the plant cycle efficiency f both stages has an ‘A. Dalton’s line © Jonval’s line efficiency of 90% and the heat addled to the boiler is 3500 KW B Willan’s tine D, Rankine tine Neslect pump wor. ‘Answer: B A ios ©. 40% B aN D. 22% 40, Dry satura cam ata pressure of (24 bar) 0.24 MPa is tapped off Selon he inlet branch of a low pressure turbine to supply heating steam in a Wt We {ontact feed heater. The tomperatre ofthe feedwater inlet othe =O heater is 42°C and the outlet is 99,6°C. Find the percentage mass of (0:9}(900)+(0.9)(500) on eee (900) +(09)(s00) Steam Properties 3300 ‘Steam at (2.4 bar) 0.24 MPa: 2036+ 368 os ike Water Properties Water 22°C Water a 96°C 34, The flow tough the note 758 kine 7 ike A. fsentopic C.polytropic case B icobarie D.fovolumic D. «5% Answer A Yao 35. Ifthe reservoirs suficiemly lage, the nore inlet velocity is Se A maximum C. negative (0g) (1-12) = (Bem B patie Dizeto 15) (1-1)(1758) = ()(412) panne = 0.095 = 95% 36. Asteum generator hs an exit enthalpy of 3500 Kika he rate of 15 ‘gis. Catelate the heat lost between boiler outlet and turbine inlet if tne enthalpy available atthe turbine inet is 3200 kl n= 4S00 KW C.=S700 kW B -2500 kW. D. = 7650 kW w “ME REVIEW ONLINE POWER & INDUSTRIAL PLANT ENGINEERING “AL ENGINEERING REVIEW "PRIME S SUPPLEMENTARY ENHANCERS STEAM POWER PLANT ) 4 J to lower the temperature of air passing through it 46. In case of steam engine the cut off ratio is the ratio of ‘A. pressure at cut off to supply pressure ©. Aicdefense pressure at cutoff o exhaust pressure 7 dé D.Aireyele (C pressure at cutoff to mean effective pressure Dfncon of pst are ofc he son Res treed wen eof‘A. maximum B. positive Answer: D 36. A steam gencrator has an ext enthalpy of 3500 ki/kg atthe rate of 1S ‘kgs. Calculate the het lost between boiler outlet and turbine inlet if the enthalpy available at the turbine inlet is 3200 klk. A. ~4500 KW, C= S700 kW B. -2500kW_ D. ~7630 kW (exunernis Gere cot ss RUT TEL Oe __PRIME REVIEW ONLINE [MECHANICAL ENGINEERING REVIEW 41. Mechanism designed to lower the temperature of air passing through it A. Aircooler © Air defense B. Airspill over D.Aireycle Answer: A, 42. A75 W turbine generator has a steam of 12.7 kg/kW-br. Steam at 123, kkglem gauge 55.6°C superheat. Exhaust 50.8 mim Hy abs, Find the ‘combined thermal efficiency ofa simple vapor eycle imcomporating this AV 12.3 hyfon? gage & 53.6 SH: 927 kirk AL S0.8mm Hg abs.: y= 160.5 LiKe A967% ©. 11.64% BI2IS% D. 10.25% Slatin €, = 0.1025 = 1025% (ams) 43. A liquid boils whea its vapor pressure equals ‘A. the gage pressure . the ambient pressure 1B the critical pressure D. one standard atmosphere Answer: © 444. In cogeneration plant, steam enters the tubine at 4 MPa and 400°C, ‘Que fourth of the sean is extracted from the turbine at 600 KPa pressure far process healing. The remaining steam comtindes to expand to 10 Kpa. The extracted steam is then condensed aad mixed with fccdwaler at constant pressure and the mixture is pumped to the boiler pressure of 4 MPa, The mass flow rate of the steam through the boiler is 30 kps. Distegarding any pressure drops and heat losses inthe piping, and assuming the turbine ‘and pump to be isentropic, how much process heat i required ia kW? ‘Steam properties v4 MPa and 400°C I= 32136 ing 5=6,7600 kine K 1000 kPa 1.9312 big 288 Khe A. 15.6468) B. 24082 D. 1102690 Selin ©. 35785 Solving for, Move 32 x@) | ¥0) t1932| 67056 1.93124] 6706+ sass | 263 = 616 [+ 715686 1b, = 5,9 = 675909 = 276075 Whe Ty = gas = 670.56 KI thas Q=m,(b,-,) a= Hnjerazs 056) (= 15670425 kw (asa) 45. The lowest permissible water level ofa boiler without intemal furnace is the height of the shel. am cus BB D. 1s Answer: B e © 30 Gs) 10:33 a ai(ig)+ (=m )Ban = (on) + (t-mj(t7ss)=(I(417) m= 0095 = 95% POWER & INDUSTRIAL PLANT ENGINEERING RINE S SUPPLEMENTARY ENHANCERS STEAN POWERPLANT 46, ln-case of steam engine the cutoff rat is the ratio of ‘A. pressure at cut off to supply pressure B. pressure at cutoff to exhaust pressure pressure at cutoff to mean effective pressure D. fraction of piston stroke which the piston has traveled when cut of Answer: D 47, Mixture with 70% quality at S00 Kpa is heated isothermal un pressure is 300 Kpa. Find the heat added during the process. ‘41 500 Ka: |= 18607, = 4.9606 At 300 Kp and 157.86°C: 5 = 7.0888 KU/kg A 14592 ug ©. 453.68 kay B. 78154 ekg, D. 865.43 Kikg Sutton For isothermal provess.T = C of t= ts Q= Tees) where: “88s 8607 + 0.7(4.9606) = 5.333 Q = (151.86 + 273)(7.0888 - 5.333) = 745.97 Kikg 48, The iscutropié efficiency of arubine is given by. (oe ‘A. ihe ratio of actual vo ideal energy extracted the rato of etal of ideal energy i 49, Caleute the time that wil tke to boil 1.2 kg of water inside a container considering a constant supply of heat at 1.25 KW is supplied to the container. ‘A24 bes ish B32hes D.O6he Sten Com, ote H(i 7 Put ee) 10225) 0 9166:721006 ir 50. Steam tht enters turbine stage hasan enthalpy of 3700 KUkg and a ‘locity of $0 mvs and it leaves with an eathalpy of 2868 Kikg and a ‘velocity of 128m/s Compute the work dane in kW given thatthe rate ‘of asteaim flow through the tubine if 0.44 kes A ast kW C3120 kW B 370 KW 43 504W See hokE, =o KE, ew 207 a AF 700+ OO 25542 oem wast ke wen =(oau!®)(mu2) asesotaw =o. ‘Please log-on to www primerevieweente com forthe enhaneemeat of lements(Terms) in Mathematies & Basic Engincering Sciences, Power & Industrial Plat Engineering and Machine Design. 6 OR PDE OSAROMTONQUERASTS CERUCETY TEL WO 02 A175 MAMNLAS SCPE COR R PAPA RSH LOYOLA STS SAMPALD NILA TL N.02 3590078