Thermal and hydraulic machines - temi d'esame svolti, Prove d'esame di Macchine

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THM Sdued Exems 4) Design : "VaV,M, Fly open; Vj dog *Steam quertor: n= wot/h; fo= 450 bar | to= 500%; 1,99%; Hi= us tg * HP turbine : dy,= 0,95 "LA durine i 197986) fu=905 bar * Thermal User: My 3 20t/h; pu =20bsr; sAureted liquid OF-Design x + Goseming by reducing He Fuel mass Flow rate loy a 10% * Constant mass Flow rate to +he thermal user Datermine . » the, off-desgn plat power ostput » He off-design. glaut overall efficiency (wii = 0935) The. cyde is: Using He. rolier diagram 7 ° go doll mine Ure. operstara I: ${R5= 450 bar *_ 3310 W0/K re Te pr 6,35 W/ È Da'= 0,023 mg * Ù = 6354944 ® MS 2902 UI/Ug — 3=65 UIMGM Hip Sito vi= qUm Ug M=0,05bar = hs ssa ee vanga P hd = 995 (19 hi las (I — is) = 2404 US wefpa=pr =%b% > hi = 908,59 0/9 e i * Ul Ap pico =90Sbar > Wi = 13%,94UTM9 mai = i at = 200- 30 = AM04/N ee Cid (6h) + ve (i) = = FE [100 (3310-2373)+ mo (2838 -2404)]= h3,35 MW af= wu (We 2e 200 (2998 - 308,59) = 49, 2h MU tit tto VE _ 20. DOLSI TAM 438,98 = 1,3, 6h UT/K9 up @it= velte(Vo- Ma) = 2 Sto (9310- Pu, 6h) = 156,36 MW Gia= gray Hi » mt td 310604 “ Bf «636 lo = et 15696 4925 9,343 DIV of -Design rap is. reduced by 10% > 4, = 0,9 nb = 9,9- 3836 = 3182 4/5 Qua = pr Hi = 93- 3488-55 = 444,26 n Cin © Me (Io la) “rive (ho — steel Le) = ve ho — clip he We Know tt hi, = hi, li = ht We urant et ru a  o 2) Des: uu *Va Va Vs Fully open; Vi closed : Caio; u O Steam generator : wiiz 4304/h; TINI x 3 HI = obar; teus; =03 In «He torino : ]9=9%6 D “LP turbine : lg =9.86;pf= ,0+bar «Thermal user : 194 = 604 ; gii= tobar,; seturated liquid OF- Design: Determine: *.f = Au0ber , t,= 500°C + riu in off-desin “ Miue 5 vare / vb E 4,216 8 “a n S- design h From dhe, Malier degni o =320% USM g& ° ee aiober 5 DE=0, 02h m/Ug SÉ= 6,3 UI/MK * Hi sf Sii er ii = i - Tae (Mò hit )= 2851046 È =28351 Dif= 9/40 mk Ss MiO a sÉ= CA Nek uffa = 0a pt =307,S3U7%6 7.5.0 Ma 7 lo gota = fa > Mis 109571 LSP = 903 bam \ 143 384771 Lvse Mi= 1930/76 = Wi Von (Mi iis )= 2143 UU Val = Mite - Mu = AZOt/M Loetnirani Wal= 922 (,10(3207- -2835)eno(1035-219)]F pt-1 Qi = at (hi-hi)= (2935- Saia i suaiaie — p39asSMW E ri a up ii — 60900594 A20-163,38 Vin = SEME ts = MAL 0/6 Gin = aste (ME - Nt) 12° (3208-144,32) = 139,9 Mw *_ agi -__ 39326. b- a "Re © are s08 7 32? ln low. 93 93 Oft-Design - tayp = vago = AOt/h |; ace = 4,2 606 = Ah £/n * New operstinal point 0: fo=-00bar , ta =S00°C of fe = -obar 3, Mo = ISU to =500°C Da = 0022 v/Ua So = G3AIVI/GR Assuring HP turbine chelfed [oolh in design and off-design: cuele® cui ru MEL - 2031 HM più We went Yip =" Vhrolting st Vi : pertt, re RT om 4199 ho hi > AUo=p' > p'=pe Free 0 ‘703,4 = 1241 bar 1 i Ù = 424,Abae So = bh W/M 0'{ Ph 23925 Wal > 03'=0,025m/o wi . * x Lui * [ea > Increase, & ss nego "ugo rollin + UE e x wing LP +ubine choked ene nd off design : alta Mu fx fu (ara Wai, saerae > ' . 2 2 ez 3) Desin: -VViM Fly an ; Vi closed «Han geeator : inite= 200t/h; pi = foca} L= 5080; t= 160% ; W= 0,3 -HP durbine : fi= 102} 1,=985 LP tubbine : = 907087; 5=0,96; vai = 120 4/h ‘ty =1%0°)",=0,36 oF-besign Determine : + Vaie) O - Pe (- const > p ge ei) Pa ti= cost, pi= const) -b gf fe=totec = x _O,/Ch2 ma /Mg E oe e x WINGK # (Fi =opor È na SE= bAZVSMI lu 2A hi 1 Tae(i Hi): =2928 KI/Mg d di93 mk fe: ci di at LE = 2929 > = 69 VI/ UK Hi =199,85+ pe =3390 W0/Kg vs. so 7 affzda > Me INA + o 50327, afosa uefreggrer hi, 236546 Sist = #62 fa=0%ber se = 2A L =163,33/V [Fg li =1927H6 hi = (It ht )=20617/6 ma = raf — af = 00-40 =80t/h Pu = eine (46 -hi) e (hi -hE)T= -2% [200(3100-2325)+ 420(3330-2506)]=52 12 nu Qi = rt (t - it )- 22. (2900- 50332) = 53:30 NW vis ff argo dsc da = ra (hf) = sedavoo 29952) = 1422SNW Gris = = wp 5( Né N 5 eo se (33%0- 2928) = = 14,33 MW Ri het * è + @É 5 = 193,25 +14,93= 196,324 ur 50,9? 0,35% $i Ga” API_SHI7 o dn A 93 OFF-Design: * Map =92 rap = 966/h an, 98 va = 6Lt/h * ha = hi = 503,629 To reduce ru ue cam Hrdltle, at Va. (Keeping O'contitions and pt) To reduce, rip we con Harolle at Ve. (Keeping G'cmbitions and pit) Assurivg bolla HP ad LP cholled both in design and off-desin: up = May +razp = 1604/h Mrup _ i o” fl i rueloaos _ mito lea e = sn Pe = 6hbar > = 90serl/e Oint=3u00us/lg P so = 48343 Maffinioi ge = hug = 28909 ha = ho — Tae (Mo - ns) = 236#4T4G H{fe =10bar Va Va =0,23v/kg hu = 296710 P_Su=6,9240/4% afft- zio — Va-0,h2w/kg hi =333010/6 7 Sa=4,324K0Ugk QX =0,0%bar bus = usff= e 12 NI gps ULROMIMG lm = ha - Tarp(e-hu)= 25364546 ® Ni . AR 3 . le e mote he _ eu Solta de 48% — 299 520/45 =h% Rito hu) + re (ha-hx)]= 4 [60 (3400— 2968)+36(33%0 — 2536]] = 39,75 1W =p2° Gin > Vup (né - ln) +rme(h& -hu) = 422 (3100-239952) +54 (3330-2968) = A18,s6r1w i - l)="£2-(296-503,42)= 13,9IM% 39,85 = n” ALEs6 ug 362 % How 95° 5 Of-Design : Vus Via = 306/h wup = 80t/h Mayp= PAptriu ya e We need to 4hrotle U, to the Hs conditims. dhe same as design: hy,=h#=260 KI7%9 f. Maw ha + Mep «ha di mE rig TIT he lin = 99/9 N BAance + the Be-SuerMenter: rin he + (rp rep) hy = why => o Puo his = (194e 11) up Fupriru P) unUnomm To lower rip end raue, Keeping rue constant uve, con trote Va and e Trerative procedure do determine rie, Mu, hu © Guess a Po reo |150 |182 | 154 [Ton © ie=vale È (HP unted) 1933 [164,3 |143 [1082 (/M] 9 off zar = 6,341 | 6,06 |b,0b|6,06 ou] O uff tte =huss 265 | 25%0|2561|2269 [kr] © = ho - lare (hola) aut |2665 |2663 [264 [074] © rima Pel (ee ha (62 134 |1,943,2|90] © liue= urne rim (=?) | [1569/148316] EM] tV  = f vA52bae. ) \m=2663 7/6 ufe Las frup = 168,3 €/h ; |M, =1,32 E/h Viu "266314076 va Arti LP turbine. Abel : vaLe II pu'vH' -nblenvs 1 ao hu =hu > fava = pad / pu=g pre E ay E ‘rue [mi gf PO (28.,). tea Pi" 10 Ei -12= 2,8%bar ì fu = 9,2tbde '- 6,40W7, Hihu= 66310716 © I 7 AG kis o, = hg = 199249745 lx = ha — “Lore (hi — huis) = 9071 Pe = "lo [eve (ho-lu) + up (n — )] = 34,200 Qua = rue (lis — him) = Ad = bo ny in= ve (th0-hn)= 124,34 MW fe n lang o lov  AI =Mup ay — ap = 22,At/h A = (Mu0+ 0) (hu'-L)= 80,95 UK Au = Qi = 8h MW n= GX = 195,19NW = al = 0,32? Me ew x LS = le-'o __ 9,14% We  6) design: “Va, Fully opta; Ve cosed «Steam generator: ruig = 4806/h (S= sober bo=S0SC; 1,=0,30 "HP turbine : 4g = 982 «LP 4urbine : fg=915; pi=00%ba H L “Thermal user: vaé = 94h, ghi =20bse 5 086; tu, = 100% OPF- Design: Determive: -V3 Meotling > rut,tub “Me; <P 5% - pu = 22bar ) 6 hò =3M0 ur h ufo L SIE Dr Dda = b 35 IM ui o Mat moli =2905 KI/4g hi = ho- - Ware(he- hifi) = 229% Mi =Obar. UU i=-9442/U9 WIR one, P 53 = 635 USM L bar : i SE fuga ri 1015 016 Ai eenline)o MAM) = 255 07/6 =39, 66 Mw bf rg hu, =h49,06 UT Rx = (Mk - hh )= 550 n La” et Pn =4638 7/1 Ri = raf (M6- ht )=454,65 N a ef vaip= Pip = mi, = 00 {/h Î= x = 0,369 se cai * hi= reualici Pine Mi = 233,020/%  +) De sign: Va,Va Fay qu pertialiy del Steam generator: fap= 3,3946945; Hi= Sang, Vite = 1804/h; Pe=td0 har) = uso": 4,=990 <HP buone : ‘tg =9,%6 *LP hwrpine 199 = 926) fu-90v+ bar * Thermal user : Qu= 32,SMUW/. 04" %0bar 020,96} Hr: satveteò onditions OF Design eno * Mae "Irap Determine : «ni, Qu) Pu) "lg “throtiling on Va. (to Keep te same, pressure at ine, HP iuvbsine, outlet) » Ma 5 vinto - rate fS=tt0bx i *-h59°C . Qin = vaio (3 fem Sen delitto > =» n= hf - 5 = 240 IA ® US- 9021 r8/ sÌ= 6,3 KI/MK Hi Le per n, = 909,59 UT/U9 e «fpr=corera, v.s.@. = h_= 168, #7 UT Ale ‘o A Hi= 439,93 MW cha)» av Gi- LAA LUI /Mg x» > Me NE Pata; WA = app = SIt/h a af rat (0 -h&) > ht= ht E = 2292 17/6 Iteration do find pu © Guessa pae (32000) | 22 | 2 © ui fee: Grin, PM 2800 egNS| 2995 @ulf= a 9) 2351 | 2340 278 O hit = 2820/14? x| x > pe? 2bbar » (pizzerie “i Coe g09s ri Mit = 299200 © Sita Gia UTI pu=9g0+bar a Mis ora auarcimgy P Mis > 13357 /Mg cd n= ha Ag nit-hd) = 21/1 Pi = [ev (lt -1*]+ FE (ht) = Lo, sa rw ‘= «Le = F- OF£ - design : «pe = Ot = 16247 vi + tarottling on V3 gu = pi To reduce vaup we reed to +lrotle VW We assume HP twloine diclled bolli n design and off-design: cf. » map 3 » de Sue. ci e'=102bar appia = US I” hho= 3210UT/% — S0=6,35 (9 lag TE lnts = 28284071 o = as % lari = ho — “le (lo -hat,) = 2291 47/4 nti © =90561/M n IR: =2ZAUI Mb 5 = 6LS WU 2) Design: “Va bosed +Skram generatori rano = 200t/h $=sobar, 6 = soc UT + HP burlone PA =d0bar" piso | «LA hubine : pi =9OSbEC: fuer = 2bar oe-Design: *Harokling on VA «Pup = 4251605 30 We 7nwRW7 si fs SET —» SE = 6,94 otok v$= 903 Mg Hi tfr a, PIER Ins UTNG 18-17 Toei his)= 3201 0/1 è QAS #6. “ionony PE: Sola 3 5 Pigostor St rpg? bi> = 245170746 duo (6 -bk)=59 sii Vik= ni Aa.g(h%- ht)= 23010416 af = (up (h3- ui)= 19Z04nU/ | Pi=gvr UÈ = 133,99 Mg v:3.0. la=W È = 0292 OR — Design +throtling on a > Ri "Pup = 4,25 1 = 2504 Mep = TAP ( HP_holted) > ray, = Me — up = SOt7/h LP hnoked = Meplpiai_ vi Ttertion to Fid pu: Devess è (4. _(>t0ba) rail [ui 2 26 Po fl =uss2 ele mi Ciel © Vis {7-69 Mes 3444 3225 Crus) Dia hd agg (1) 3225 3262 {4376] ©hi - hu trup + ht rva vice 326L RIL Lo) © uffi ur ALI? 912 D/6] ha --- U © SG = 264200 7 3 AST Ab Vv CRSe] DU= 26685 (<P = 3h UP sHII Uolled) hu = 3262 W/M. > lan'=323640/45 uf Meize — Su'= 9,08 VIAGK a = 32M Vis {Be 905 =D huis 221 bo Tg Su' = DOLUTMM = Lage (ls) 1901074 Pu = "tofu (iS - ha) + ep ('- hu}}= 42,63% Qu ring (M8 ht) = 228,33 MW g=% te = 9286  2) Francis Turbine o *olky=20 ) Ca=25Mm5; Ma=Abra/s M77O/5_} Ca» 23, Aa = 9*+5 Aa OCF- Design: - n'=98n -Q'=a “No ‘ncidence, > Wi! 1/ 4) Dog UU = =Ww=0,95S ; = Cam e 4 7 Lug z Dedenine : Mw 30 + Q=C4gA, = Ca. fa = ha 4-1 =D Ca =Ca = Ca4: 3 SinAa * 63#S = hi m/6 Wan, = Ca COSÙA —AU4= #,5 m/5 074 = {Wat + (Ca Sino)” = A1,3% m/5 = (tut = 451615 ag = Wa: Sì Ba > Ba arese) =AMSA (Cso). 18,72” B2- 180- ansin (SG) = 134,2° SE-tebgn n'= Qqn xD TC Ma = 98 My = AT 65 S 4 = 0841, = 8,0 14/5 4A 5 N. Tncilence =O =D UV U wa Ba = pa = 39° Wz' U 2 D Pa'=B2 = 434,240 I a'=Q > Cs =Ca2-03S The add adlociica sii Ani sare Le cai conditions ie Cha soa > Ca- Sind,= 9,55 m/s (DA =, = Cag = 14,1 m/ Wi = vw = 14,33 0/5 ; = Wy= 15,1 /5 Cliw= Wa" cospa + = W923m/S Ca={ChT+ Pure 22,02m/s Gi ci = (aree - 415% rs Li = Mica = by ca = 285, bl T/Ug Losses : = Wil — as = sug Y = 2m/s (A Lasiye = È (1) 2649744 dr1 Lee (de) 4 7746 Vena = cui = 1,9%-3/Kg È La 9 8713 ly= 4y =  -3_3 =—|x= 23:40 5 Vex= Ven = 300-100" Va= Vesta) = 242. ag Mor Bart = 8,6340"m° The vdumetric eRicienoy is: ne le (0) BRR - ga The, mass Flow rate is var = dr Pe Von = Mu Vr -7E= OS Tntemal work : Pi= Li-m = fon >» Lie Fesnoo = 132, SPA US/Mg x FLY between 4 vip: Re rLi=phv QE4 = Leg (T2-T) > Ta= Titti = h24,984 LeA !s now work. n. tue second comprester: Be=3; 42336 Continvity >» rag = le Mr = 0,054 Ug/s Volumerric. efficiemoy Aug "de (1-5) dea. le (6-5) Ur deine) rt “> Avg -le (4-5) i (179)- dat "]-0,899 Dispecoment: rig = x Fe: Veg Me sy = Fg - 1,3361088 = Ver (4) = 2,048:40%3 va peer Bini” " h,h33/107" mi  Lair] =2t esp] (4) - 63354 Le fex ne ber 1308,22U7/%9 n Lis = Ta (e&#-1) - 23071016 ‘ Sg La;is Lis = Ta: =0,83L Compressor eFFiciency : e È Us: ‘la: o =0,#?62 99  ORF — Desson Res c Ugg v u ATVEMET SIENA 4 de SRI = valve Ì Ì a O" Resencir » Simply converge È nozzke Pa =Azbar (undrengeà from desgn conditions) Tier Refrigented compression : fu >; Pe= lho {E du= "hp 1-1) TAO. =leli-S) [A+ )= (Be gugf”) risi Ver fa La else E uri ar = le mr Nozzie, : rirozzio( Ta _ riusezie IRTA Ls RE È -T.= Ta ze 1° LL Minozzle From continuity : ig = Mroezle È 2 =D T=M (fonte) mr Tiemeti cp N(Acc ber Li>o\ Tar si e dò SEA Lenz, ma [(R) II 77)  3) Contrifugal TurboCompressor + Roots. Motor “Qa=Abac ; Ta = 293K 2 - pu = pa=Abac ; T=Ta= 293K * Tipocompressor: radi blides ; (O: d2=2/9mm > ng = 20000 fpm n Vo=293U / fe =4bar ; Nn=22000rpm * Roots Motori ne= 1850 pr; Ae 3938; b=52Sw ; P.= 6004 infinite. 3 Determine : the Cowpressor's working. point * Pdos ) Ca (Rats lome) > Cr max (with n vncliseged) 8 Na (hem Caex) n_ R/R=- Comtrifuaal Compressor =» Giu =0 Radi Iolades > Cu DL: = cent cafe pri aa 63, 6h WO/%g Li=cp(re ma) > tate = 3564 wr ViM 6 È 4 03 e Ac fa ne ue=3 f3 Vo kb So = A ER Aa RT 60 iii  h) Het Ehmgert Filter + Tukscomprezion . Pa =402e } Ta=293K + Q ge PSMW 4 . E = £5000 2 A ax } Pasta =fa! Am =98+ mune . U=4,0; R=28/k9K Determine : Ps > Be. ul Ta'= 229K ae Ta) = 40,95 DT. dI Sg = 132166 L = % EU cir )-% lm 2 or (E DE 66, T3UI/Ug Li=cp(73-t2) »imon'+ 2290  6) Tirbocomprestor + Heat Excanger + Rodts Compessor * Cp=1004,5 V/M; R=297I/GK 2 - = Abar ) Ta =2934 * Operating Rint: E Te ge) _ . matta 7 "le=0%; a =M65; = 9,35 K st * T3=300K + Roots Compressor: de 0,32; iVo= 3000 * fut bar Determine : ne. ; CR Of-Deston : No heat - exlanger - Ay=const;, p,= const Determine : new operating point ; Ck = î IT 4,6 oa > Me 0,269 Us/s Continuity % Mo=Me f- = 2,35 = Pe=p:= fe cpa= 2,356 Roots Compressori Le =iV(pu-ps)= h95 I/cyede Me = Nu: fg AV Di = E Ao mae: R- Ta =—DNr = 60. Ty - P3 AV = 233+ cpm Pi= Lc: g= 22, S8U% Pas = G = 23,29UW Ps = Cauas NET = (Cp= Pabs. 220: 94,22NMm OF - Design "n dd Qu Ueep constant -Iy iS constant ‘ point 2 and 3 are coincidemt el e Continvity Mi = MR ne ù i te Ueeps constant from desgn —> the now pperatvig pint says ) ; n ine same curve . ' Pei ivo ny Late i 88 vas a ' I (2) = CC.) ne fl STA Sa —> Tierotive Prowess : Neg Qperatirg int @ Guess 8 civ veve h)0 3,4 3,4 © dii -L. (vane) 0,23, |0,24 [0,199 1 f © Find Pe, “le nto |feszh |fe=735|G23 charèck. Lego interes 1 '_aah|Ac=9|x=033 © LI = fe coma (pe 9a) 109,6, |106,6% [103,65 ' Q T' =Tn te L0z,2 399,2 396,2 © rig =dv be ivo n 0,205. | 0,202. | 0,199 D ara? x |X Tv %) Contrifuza Tuisscompressor + Refrigolor + Roots Q -pa= Abar., T1=293K ; gr eta ) fa = Ps * Roots : Vo= ded ; Ng.= 3433 cpr Pas Determine : Qu A Han duo (TT) Lem te) Roots: Gap pi ve eoe - Prev fune 60 TS 4 Li. = @(-t)> * cata (BE-a) uo = lac = Ae Lie = Ae FLT (4-3)-Qe+Li.= 0 Ù ld  2) Conkifuga Tirbocompressor radii. blades To=293K } fo = Alosr) No = 20.000rpre z Stat i - nho=41 ; d'=0,249m Esp Tan, Pu =0a = Abr , Ta = 2934 Roots Motor: ng=1850 rem Xv= 0938) Ve=S Sd = 600w 1 2 2 Pai fine Roots Moler: <A A_ fa NR ot ei ee Conkinvity : mac Turbocompressor i Mo=4,4 —» NE 1/-n0= 22000 cpm Ceubrifugal + Cas0 Radial blades » Casta Lie Cau My —Cuen a = mr my=vr'en E d'=252,240% | L= ut = 6360447 A e, exit of que infiarte, sol ei i FIT(1-3): Lr 03m) DTT = Mme Lie as,,hk Fu E Ve = 201 » MIE -0,2067