Enye yezinto ezisetshenziswa kakhulu emhlabeni jikelele ukukhiqizwa kwamandla kagesi ophehlwa ngamanzi yi Francis ephendulwa. Iwumshini we-turbo owenziwe nguJames B. Francis futhi osebenza ngokusabela nokugeleza okuxubile, usebenzisa ukunyakaza kwamanzi ukukhiqiza amandla. I-Francis turbine iyakwazi ukusebenza ebangeni elibanzi lokuphakama kanye namazinga okugeleza, okuyenza ibe inketho eguquguqukayo futhi ephumelelayo yezitshalo ezihlukahlukene ezikhiqiza ugesi ngamanzi, njengoba ingasebenza emithambekeni esukela kumamitha amabili kuya kumamitha angamakhulu amaningana.
Kulesi sihloko sizohlola ngokuningiliziwe izici, izingxenye kanye nokusebenza kwe-Francis turbine, kanye nokubaluleka kwayo ekukhiqizeni amandla kagesi ngamanzi.
Izici eziyinhloko ze-Francis turbine
I-Las Imishini ephehla ugesi kaFrancis Zigqama ngomthamo wazo omkhulu wokusebenza emazingeni ahlukene obude, ukusuka kumamitha ambalwa nje ukuya ngaphezu kwamamitha angama-800, nakuba ukusebenza kahle kwazo kutholakala ezindaweni eziphakeme ezingaphansi kwamamitha angu-800. Lokhu kungenxa yokuthi, ezindaweni eziphakeme, ukuhluka kwamandla adonsela phansi kungase kuthinte kabi ukusebenza kwawo.
Lawa ma-turbines aklanyelwe ukusebenza ngezigaba ezihlukahlukene zokugeleza, okubavumela ukuthi bavumelane nezimo zokusebenza ezahlukene. Zisetshenziswa ikakhulukazi ku izitshalo zikagesi ngamanzi ukukhiqiza ugesi, ukusebenzisa amandla angaba khona amanzi. Nakuba ukuklama kwazo kokuqala, ukufakwa nokugcinwa kwazo kubiza, ukuphila kwazo isikhathi eside, ukusebenza kahle kanye nezindleko eziphansi zokunakekela kubenza babe utshalomali olunenzuzo lwesikhathi eside.
Idizayini ye-Francis turbine ihlanganisa uhlelo lwe-hydrodynamic oluqinisekisayo ukulahlekelwa okuncane kwamanzi, okuqinisekisa ukusebenza okuphezulu. Ngaphezu kwalokho, ukwakheka kwayo okuqinile nokungazweli kunciphisa isidingo sokunakekelwa, okuyinzuzo enkulu kunezinye izinhlobo zama-turbines. Njengoba ubuchwepheshe buthuthuka, kuye kwathuthukiswa izinto ezintsha eziphinde zinciphise izidingo zokunakekelwa, okuvumela izinjini zomoya zikaFrancis ukuthi zihlale zingabizi amashumi eminyaka ambalwa.
Omunye wemikhawulo ye-turbine kaFrancis yiyona ukuzwela ukwehluka okukhulu kokugeleza kwamanzi, ngakho-ke akunconywa ukuyifaka ezindaweni lapho ukugeleza kungahluka kakhulu.
Ukuhamba ngomkhumbi we-Francis
Esinye isici okufanele sicatshangelwe ekwakhiweni nasekugcinweni kahle kwama-turbines kaFrancis yile i-cavitation, isenzakalo se-hydrodynamic esenzeka lapho imigodi noma amabhamuza omusi akheka phakathi koketshezi. Lokhu kwenzeka lapho amanzi edlula ngesivinini esiphezulu emaphethelweni acijile e-turbine, okubangela ukungalingani kwengcindezi ngokwefomula kaBernoulli.
Amabhamuza akheka, aziwa ngokuthi imigodi ye-steam, hamba ukusuka endaweni enengcindezi ephansi kakhulu ukuya kwephezulu. Uma isitimu sibuya kungazelelwe esimweni soketshezi, amabhamuza ayawa futhi akhiphe amandla, angalimaza ukwakheka kwe-turbine ngokudala ama-microimpact ezindaweni eziqinile. Lesi simo asigcini nje ukunciphisa ukusebenza kahle kwe-turbine, kodwa futhi singasheshisa ukuguga kwezingxenye zayo.
I-Cavitation iyi-drawback ngoba inganciphisa impilo ewusizo ye-turbine ngokukhiqiza ama-microcracks kanye nomonakalo obonakalayo, ikakhulukazi ezindaweni eziseduze ne-rotor. Ukuze kuncishiswe le nkinga, kusetshenziswa izinto ezithuthukisiwe futhi kusetshenziswa izindlela zokuvikela zokuvikela, ngaphezu kokulawulwa okuphelele kwezimo zokusebenza, ukunciphisa ukuhluka okubangela lesi simo.
Izingxenye eziyinhloko ze-Francis turbine
I-turbine kaFrancis inezingxenye ezahlukahlukene, ngayinye igcwalisa umsebenzi othile wokukhulisa ukusebenza kahle ekukhiqizeni amandla kagesi ngamanzi:
- Igumbi Kuvunguza: Leli gumbi lisakaza uketshezi ngokulinganayo ku-impeller. Ukuma kwawo okuzungeza noma komnenke kubalulekile, njengoba kuqinisekisa ukuthi ijubane loketshezi lihlala lingashintshile kuzo zonke izindawo. Ivamise ukuba yindilinga esigabeni, nakuba ingaba unxande kwezinye izimo.
- Umsabalalisi: Kwakhiwe ama-blade angashintshi anomsebenzi wesakhiwo ngaphakathi kwesistimu. Lezi zakhi ziqinisa i-spiral chamber futhi zinciphise ukulahlekelwa kwe-hydraulic.
- Umsabalalisi: Lesi sigaba sakhiwe ama-vanes ahambayo, alawula ukugeleza kwamanzi ukuya ku-impeller. Umsebenzi wayo ukuvumela ukugeleza kulungise ukulayisha ukuhluka kunethiwekhi kagesi, okuthuthukisa ukusebenza ngaso sonke isikhathi.
- Impeller noma Rotor: Lena inhliziyo ye-turbine, lapho ukushintshana kwamandla kwenzeka khona. I-impeller iguqula amandla e-kinetic, amandla namandla okucindezela kwamanzi abe amandla emishini. Ngeshaft, lamandla asetshenziswayo adluliselwa ejeneretha likagesi, lapho agcina eguqulwa abe ugesi.
- Ukuncela tube: Lona uketshezi oluphuma ku-turbine. Ukuma kwayo kwe-diffuser kudala i-vacuum esiza ukubuyisela ingxenye yamandla engazange isetshenziswe ngokuphelele ku-impeller, ngaleyo ndlela kube nesandla ekuthuthukiseni ukusebenza kahle kohlelo lonke.
Ukuhlukaniswa kwama-turbines kaFrancis
Ama-turbines kaFrancis angahlukaniswa ngokuya ngesivinini sabo sokusebenza nezici zekhanda:
- I-Slow Francis turbine: Isetshenziswa kakhulu ezindaweni eziphakeme zokugxuma, ezingaphezu kwamamitha angama-200.
- I-Francis turbine evamile: Ikhonjiswe ubude obuphakathi, obuphakathi kwamamitha angama-20 no-200.
- I-Francis turbine esheshayo futhi esheshayo: Ifanele ukugxuma okuncane kokuphakama, okungaphansi kwamamitha angama-20. Lawa ma-turbines alungele ukugeleza kwamanzi amakhulu kanye nekhanda eliphansi.
Ukwakheka kwalawa ma-turbine kuyahlukahluka kuye ngezici zekhanda nokugeleza okutholakala ekufakweni ngakunye. Kubalulekile ukukhetha uhlobo olufanele kakhulu lwe-turbine ukuze kuthuthukiswe ukusebenza kwamandla nokunciphisa izindleko zokusebenza.
Ngolwazi olungenhla uzokwazi ukuqonda kangcono ukuthi ama-turbines kaFrancis asebenza kanjani, izici zawo eziyinhloko, izingxenye kanye nemikhawulo. Lolu hlobo lwe-turbine luyinketho eguquguqukayo, esebenzayo futhi ehlala isikhathi eside yokukhiqiza amandla kagesi ngamanzi emhlabeni jikelele.