Xisaabinta Waxtarka Kulaylka ee Matoorada Uumiga Casriga ah
Matoorada uumiga waxaa badanaa loo arkaa tiknoolajiyad "caadi ah" oo ka timid Kacaankii Warshadaha. Si kastaba ha ahaatee, mabaadi'dooda iyo horumarkooda ayaa weli khuseeya maanta, gaar ahaan warshadaha korontada ee dhuxusha lagu shido (PLTU), rakibaadda kulaylka iyo korontada isku dhafan (CHP), iyo nidaamyada marawaxadaha uumiga ee warshadaha habka. "Matoorada uumiga casriga ah" waxay tixraacayaan nidaamyada korontada ee ku salaysan wareegga Rankine, kuwaas oo aad uga waxtar badan matoorada uumiga ee dhaqameed ee isdhaafsada, iyagoo adeegsanaya cadaadis sare iyo heerkul, kuleyliyayaal sare, dib-u-kuleyliyayaal, iyo kuleylinta dib-u-cusboonaysiinta iyada oo loo marayo kuleyliyayaasha biyaha quudinta. Si loo fahmo waxqabadka nidaamyadan, hal halbeeg oo muhiim ah oo had iyo jeer la xisaabiyo waa hufnaanta kulaylka.
1. Fikradda Aasaasiga ah ee Waxtarka Kulaylka
Waxtarka kulaylka ee matoorka uumiga wuxuu qeexayaa inta tamarta kulaylka ee la geliyo (laga bilaabo gubashada shidaalka ama isha kulaylka) si guul leh loogu beddelo shaqo waxtar leh, badanaa qaab koronto oo usha turbine-ka ah ama koronto dhaliyaha. Guud ahaan, waxtarka kulaylka waxaa lagu qeexaa sida:
\[
\eta_{th} = \frac{W_{net}}{Q_{in}}
\]
Halkee:
– \( W_{net} \) waa shaqada saafiga ah ee wareegga (shaqada marawaxadaha marka laga reebo shaqada bamka).
– \( Q_{in} \) waa kulaylka soo gala wareegga, oo guud ahaan ka dhaca kuleyliyaha iyo/ama kuleyliyaha sare.
Wareegga Rankine ee ku habboon, qaybaha ugu muhiimsan waxaa ka mid ah bamka, kuleyliyaha, turbine-ka, iyo kondenserka. Uumiga waxaa lagu shubaa (biyaha quudinta) cadaadis sare, waxaa lagu kululeeyaa uumi (la kululeeyay ama aad loo kululeeyay), waxaa lagu balaariyaa turbine-ka si loo soo saaro shaqo, ka dibna waxaa dib loogu celiyaa dareere ku jira kondenserka ka hor inta aan dib loogu gelin bamka. Waxtarka kulaylka ayaa ah cabbirka ugu weyn ee lagu cabbiro sida hufan ee matoorka uumiga uu u isticmaalo tamarta kulaylka.
2. Wareegga Rankine ee ugu Fiican iyo kan dhabta ah
Xisaabinta bilowga ah, injineeradu waxay inta badan ka bilaabaan wareegga Rankine ee ugu habboon si ay u helaan fikrad ah xadka sare ee hufnaanta. Male-awaalka ugu habboon badanaa waa:
1. Habka bamka iyo marawaxadaha Isentropic (aan lumin).
2. Ma jiro hoos u dhac cadaadis ah oo ku yimaada kuleyliyaha, tuubooyinka, kuleyliyaha sare, dib-u-kuleyliyaha, iyo kondenserka.
3. Ma jirto wax kuleyl ah oo deegaanka ku dhaca.
4. Uumi-baxa iyo kuleylintu waxay ku dhacaan cadaadis joogto ah.
Xaaladaha dhabta ah, mala-awaalkan si buuxda looma buuxiyo. Khasaaraha is-jiidjiidka, khasaaraha cadaadiska, iyo waxtarka isentropic ee bambooyinka iyo marawaxadaha ayaa ka yar 100%. Sidaa darteed, waxtarka kulaylka dhabta ah had iyo jeer wuu ka hooseeyaa qiimaha ugu habboon, xisaabintuna waa inay ku jiraan xuduudaha sida:
– Waxtarka isenttropic ee turbine-ka (\(\eta_t\))
– Waxtarka Isentropic ee bamka (\(\eta_p\))
– Kuleylka oo lumaya (kuleylka oo lumaya)
- Hoos u dhac cadaadis
3. Tallaabooyinka Xisaabinta Waxtarka Kulaylka (Qaab-dhismeedka Guud)
Si loo xisaabiyo waxtarka kulaylka ee matoorka uumiga casriga ah (ku salaysan Rankine), tallaabooyinka guud waa:
a) Go'aaminta Dhibcaha Gobolka
Badanaa waxaa lagu calaamadeeyaa:
1. Furaha kondenserka / tuubada bamka (dareere buuxa oo cadaadis kondenserka ah)
2. Bamka/gudaha biyaha kuleyliyaha (biyaha quudinta cadaadiska sare leh)
3. Furaha kuleyliyaha/kululeeyaha/gudaha marawaxadda (uumi qalalan oo buuxa ama aad u kulul)
4. Furaha marawaxadaha / godka kondenserka (isku darka biyaha uumiga ama qoyaanka aadka u kulul)
Wareegyada leh dib-u-kuleyliyaha iyo dib-u-cusboonaysiinta, tirada dhibcaha xaaladda ayaa kordha. Matoorada uumiga casriga ah ee warshadaha korontada ee waaweyn waxay caadi ahaan leeyihiin marxalado badan oo soo saarista marawaxadaha iyo kuleyliyeyaasha biyaha quudinta, taasoo ka dhigaysa falanqaynta mid aad u adag, laakiin mabda'u waa isku mid: samee dheelitirka tamarta qayb kasta.
b) Qaado Xogta Hantida Thermodynamic
Hantida ugu muhiimsan ee loo baahan yahay:
– Enthalpy (\(h\)) meel kasta
– Entropy (\(s\)) oo loogu talagalay hababka isentropic
– Cadaadiska (\(P\)) iyo heerkulka (\(T\))
– Tayada uumiga (\(x\)) marka ay ku jirto gobolka laba-waji ah
Xogtan waxaa badanaa laga soo qaataa miisaska uumiga ama software-ka (EES, REFPROP, Aspen, ama xisaabiyeyaasha hantida IAPWS/IF97).
c) Xisaabi Shaqada Bamka
Shaqada bamka ee ku habboon waxaa lagu qiyaasi karaa sida:
\[
W_p \qiyaastii v_f (P_2 – P_1)
\]
Halkee \(v_f\) uu yahay mugga gaarka ah ee dareeraha (m³/kg) ee laga soo galo bamka. Bamka dhabta ah:
\[
W_{p,dhab ahaantii} = \frac{W_{p,ku habboon}}{\eta_p}
\]
Dabadeed enthalpy oo ka baxaya bamka:
\[
h_2 = h_1 + W_{p,dhab ahaantii}
\]
d) Xisaabi Kuleylka Kuleylka Kuleylka
Guud ahaan wax soo saarka kulaylka:
\[
Q_{in} = h_3 – h_2
\]
Haddii uu jiro kuleyliye sare, qiimaha \(h_3\) waa enthalpy-ga uumiga aadka u kulul ee ku yaal godka marawaxadaha. Haddii dib-u-kuleyliye uu jiro, waxaa jira kuleyl labaad oo dheeraad ah:
\[
Q_{in,wadarta} = (h_3 – h_2) + (h_5 – h_4)
\]
(iyadoo ku xiran tirada dhibcaha ku qoran jaantuska).
e) Xisaabi Shaqada Marawaxadda
Turbine ku habboon (isentropic), \(s_3 = s_{4s}\) iyo \(h_{4s}\) ayaa laga soo qaatay jadwalka. Turbine dhab ah:
\[
\eta_t = \frac{h_3 – h_{4,dhab ahaantii}}{h_3 – h_{4s}}
\Midigta h_{4,dhab ahaantii} = h_3 – \eta_t (h_3 – h_{4s})
\]
Hawlgalka marawaxadda:
\[
W_t = h_3 – h_{4, dhab ah}
\]
Haddii ay jiraan marxalado badan oo ballaarin ama dib-u-kululayn ah, wadarta shaqada marawaxadaha waa wadarta marxalad kasta.
f) Xisaabinta Shaqada Shabaqa ah iyo Waxtarka Kulaylka
\[
W_{net} = W_t – W_p
\]
\[
\eta_{th} = \frac{W_{net}}{Q_{in}}
\]
Kani waa xudunta xisaabinta waxtarka kulaylka wareegga.
4. Tusaale Tusaale ah (Fudud)
Ka soo qaad wareegga casriga ah ee Rankine oo fudud ayaa leh xog (qaab enthalpies ah) oo horey looga helay miisaska uumiga oo tixgelinaya waxtarka qaybaha:
– \(h_1 = 191 \, \text{kJ/kg}\) (dareere buuxa oo ka baxaya kondenserka)
– \(h_2 = 200 \, \text{kJ/kg}\) (wax soo saarka bamka, dhab ahaantii)
– \(h_3 = 3500 \, \text{kJ/kg}\) (uumi aad u kulul ayaa gala marawaxadda)
– \(h_4 = 2400 \, \text{kJ/kg}\) (wax soo saarka marawaxadda, dhab ahaantii)
Markaa:
– Shaqada marawaxadaha: \(W_t = 3500 – 2400 = 1100 \, \text{kJ/kg}\)
– Shaqada bamka: \(W_p = 200 – 191 = 9 \, \text{kJ/kg}\)
– Shaqada saafiga ah: \(W_{net} = 1100 – 9 = 1091 \, \text{kJ/kg}\)
– Kuleylka la geliyo: \(Q_{in} = 3500 – 200 = 3300 \, \text{kJ/kg}\)
Waxtarka kulaylka:
\[
\eta_{th} = \frac{1091}{3300} = 0.331 \qiyaastii 33.1\%
\]
Qiimahani waa mid macquul ah wareegga Rankine oo aad u wanaagsan, laakiin warshadaha tamarta casriga ah ee aadka u sarreeya ayaa noqon kara kuwo ka sarreeya marka loo eego hufnaanta warshadda saafiga ah (inkastoo ay wali saameyn ku leedahay kuleyliyaha, kondenserka iyo khasaaraha culeyska dheeraadka ah).
5. Arrimaha Kordhiya Hufnaanta Matoorada Casriga ah ee Uumiga
a) Kordhi heerkulka iyo cadaadiska uumiga galaya marawaxadda
Heerkulka celceliska ah ee ku darista kulaylka ayaa sarreeya, hufnaanta ayaa sarreysa (iyadoo la raacayo mabda'a Carnot). Tiknoolajiyada Supercritical iyo kuwa aadka u-xun waxay u oggolaanayaan hawlgallada cadaadiska ka sarreeya barta muhiimka ah ee biyaha (22,1 MPa), iyagoo yareynaya khasaaraha la xiriira isbeddellada marxaladda iyo kordhinta hufnaanta.
b) Hoos u dhigista Cadaadiska Kondenserka (Vukum wanaagsan)
Hoos u dhigista cadaadiska kondensarka waxay kordhisaa baaxadda ballaarinta kondensarka, taasoo kordhinaysa waxqabadka kondensarka. Si kastaba ha ahaatee, tani waxaa xaddidaya heerkulka biyaha qaboojinta, cabbirka kondensarka, iyo khatarta heerarka qoyaanka sare ee marxaladaha ugu dambeeya ee kondensarka.
c) Wareegga Dib-u-kuleylka
Kuleyliyaha dib-u-kululeeyaha ayaa dib u kululeeya uumiga ka dib marka uu qayb ahaan ballaariyo, ka dibna dib u ballaariya. Natiijadu waxay tahay in hufnaan dheeraad ah iyo heer qoyaan oo hooseeya uu ka jiro meesha laga soo galo marawaxadaha (oo ammaan u ah daabyada marawaxadaha).
d) Dib-u-soo-nooleyn (Kuleylinta Biyaha Quudinta)
Marka la qaato qaar ka mid ah uumiga ka imanaya marawaxadda si loo kululeeyo biyaha quudinta, kuleyliyuhu uma baahna inuu bixiyo kulayl badan si uu u gaaro barta karkaraya. Dib-u-soo-noolayntu waxay kordhisaa hufnaanta wareegga, inkastoo ay yarayso culayska shaqada marawaxadaha sababtoo ah uumi qaar ma soo saarayo shaqo cadaadis hooseeya.
6. Farqiga u dhexeeya Waxtarka Kulaylka Wareegga iyo Waxtarka Soo-saarista
Waa muhiim in la kala saaro:
– Waxtarka kulaylka wareegga Rankine: oo ku salaysan \(W_{net}/Q_{in}\) qaybaha wareegga.
- Waxtarka saafiga ah ee wax soo saarka: waxay tixgelisaa khasaaraha gubashada, hufnaanta kuleyliyaha, khasaaraha matoorka, culaysyada kaalmaynta (bamka, marawaxadaha, qalabka gudbiya), iyo khasaaraha gudbinta gudaha.
Warshadaha korontada ku shaqeeya dhuxusha, hufnaanta kuleyliyaha iyo khasaaraha nidaamka ayaa noqon kara kuwo aad u weyn. Sidaa darteed, xitaa haddii hufnaanta kulaylka wareeggu ay u muuqato mid sare, hufnaanta guud ee saafiga ah ayaa laga yaabaa inay hooseyso.
7. Gunaanad
Xisaabinta hufnaanta kulaylka ee matoorada uumiga casriga ah waxay asal ahaan ku salaysan yihiin dheelitirka tamarta wareegga Rankine: xisaabinta shaqada marawaxadaha, shaqada bamka, iyo gelinta kulaylka ee kuleeliyaha (iyo dib-u-kuleyliyaha, haddii ay jiraan). Furaha saxnaanta waa go'aaminta saxda ah ee dhibcaha xaaladda iyo sifooyinka thermodynamic (enthalpy, entropy, tayada uumiga), iyo sidoo kale ku darista xaaladaha dhabta ah sida hufnaanta isentropic iyo hoos u dhaca cadaadiska. Hufnaanta kulaylka waa tilmaanta ugu horreysa ee waxqabadka nidaamka iyo saldhigga qiimeynta hagaajinta sida kororka heerkulka/cadaadiska, dib-u-kulaylinta, dib-u-cusboonaysiinta, iyo hagaajinta kondenserka.
Haddii aad rabto, waxaan ku dari karaa tusaale xisaabeed "casri ah" (tusaale ahaan wareegga dib u kululaynta + kuleyliyeyaasha biyaha quudinta 1-2) oo dhammaystiran oo leh jaantusyada dhibcaha gobolka iyo jaantusyada T si loo qiyaaso daraasadda kiiska dhabta ah ee PLTU.
