Izinhlelo Zokushisa Eziyisisekelo Ezinjini Zezimoto
Uhlelo lokusha luyinhliziyo yokusebenza kwenjini yezimoto, ikakhulukazi ezinjinini zokusha zangaphakathi. Ngokusha, amandla amakhemikhali kaphethiloli aguqulwa abe amandla okushisa, bese kuba amandla omshini angahambisa ama-piston, i-crankshaft, futhi ekugcineni amasondo emoto. Ukuqonda izisekelo zesistimu yokusha kusisiza siqonde ukuthi kungani izinjini zinamandla, ukuthi kungani ukusetshenziswa kukaphethiloli kungaba yinto echithayo noma eyongayo, nokuthi kungani ukukhishwa komoya kungaba okuhlanzekile noma okweqile. Lesi sihloko sixoxa ngemibono eyisisekelo yokusha, izingxenye ezisekelayo, izigaba zenqubo, kanye nezici ezithonya ukusebenza kahle kanye nokukhishwa komoya ezinjinini zezimoto.
1. Ukuqonda Ukushiswa Kwezinjini Zezimoto
Ukusha kuyisenzo samakhemikhali esisheshayo phakathi kukaphethiloli nomoya-mpilo esikhiqiza ukushisa. Ezinjinini zezimoto, lokhu kushisa kusetshenziselwa ukwandisa ingcindezi yegesi ekamelweni lokusha, okuvumela i-piston ukuthi inyakaze. Ngokuvamile, ukusha "okuhle" ukusha:
1. kwenzeke ngesikhathi esifanele,
2. kwenzeka ngokuqina nangokulinganayo,
3. ikhiqiza amandla afanele,
4. ukunciphisa ukukhishwa kwegesi okuyingozi,
5. akubanga izimpawu ezingavamile njengokungqongqoza (ukuqhuma) noma ukuqhuma kabi (ukwehluleka ukusha).
Empeleni, ukushisa akugcini nje ngokuphathelene “nokushisa kwamalangabi”, kodwa futhi kuhlobene nokufakwa kwe-atomization/spray kaphethiloli, ukuxubana komoya nophethiloli, ukucindezela, uhlelo lokushisa noma lokushisa, kanye nomklamo wegumbi lokushisa.
2. Izinhlobo Zezinjini Nezindlela Zokushisa
Ezimotweni zesimanje, izinhlobo ezimbili eziyinhloko zezinjini zokushisa zangaphakathi yilezi:
a) Injini Kaphethiloli (Ukushisa Kwezinhlansi/SI)
Izinjini zikaphethiloli zisebenzisa ama-spark plug ukukhiqiza i-spark. Ingxube yomoya-kaphethiloli icindezelwa kusilinda, bese i-spark plug ivutha ngesikhathi esiqondile (esinqunyiwe) sokushisa uphethiloli. Lolu hlelo lubizwa ngokuthi i-spark ignition ngoba i-ignition ibangelwa yi-spark.
b) Injini Kadizili (Ukushisa Okucindezelwe/CI)
Izinjini zikadizili azisebenzisi ama-spark plug (njengoba kuvamile). Umoya ucindezelwa ngesilinganiso sokucindezela okuphezulu, okuphakamisa izinga lokushisa lomoya. Uphethiloli kadizili ube usufakwa ekamelweni lokushisa; ngoba izinga lokushisa lomoya selivele liphezulu kakhulu, uphethiloli uyavutha ngokuzenzakalelayo. Le nqubo ibizwa ngokuthi i-compression ignition.
Zombili zihlose ukukhiqiza ingcindezi yegesi ukuze kucindezelwe i-piston, kodwa izici zokusha, izingxenye ezisekelayo, kanye nendlela yokulawula ingxube zihlukile.
3. Izingxenye Eziyinhloko Ezisekela Ukusha
Uhlelo lokusha aluzimele lodwa; luhlanganisa izinhlelo eziningana ezibalulekile:
1. Uhlelo lokungenisa umoya: luhlinzeka ngomoya ohlanzekile ngesihlungi, umzimba we-throttle (kuphethiloli), kanye ne-input manifold.
2. Uhlelo lukaphethiloli: luhlinzeka ngophethiloli nge-carburetor (izimoto ezindala) noma nge-injection (EFI/GDI/CRDI).
3. Igumbi lokusha kanye nendlela yokucindezela: liqukethe isilinda, i-piston, indandatho ye-piston, ikhanda lesilinda, kanye nomklamo wegumbi lokusha.
4. Uhlelo lokukhanyisa (injini kaphethiloli): luhlanganisa i-ECU/igniter, ikhoyili, ama-spark plug, izinzwa (i-CKP/CMP), kanye nezilungiselelo zesikhathi sokukhanyisa.
5. Uhlelo lokukhipha umoya: lususa amagesi okukhipha umoya ngokusebenzisa i-exhaust manifold, i-catalytic converter, i-muffler, kanye ne-O2/AFR sensor ukuze kutholakale impendulo yokulawula ukukhishwa komoya.
Uma enye yezingxenye ingasebenzi kahle (isibonelo, ama-spark plug abuthakathaka, ama-injector angcolile, ukucindezelwa okuvuzayo, noma umoya ovalekile), ikhwalithi yokusha izokwehla.
4. Izigaba Zenqubo Yokushisa Ngokusho Komjikelezo Womsebenzi
Enjinini ene-stroke ezine (evame kakhulu), ukusha kwenzeka ngezigaba ezilandelayo:
1. Ukushaywa yi-Intake: i-piston iyehla, i-intake valve iyavuleka, umoya (kanye nophethiloli ezinhlelweni ezithile) kungena kwisilinda.
2. Ukucindezela: I-piston iyaphakama, amavalvu okungenisa kanye nawokukhipha umoya ayavaleka. Ingxube (injini kaphethiloli) noma umoya wodwa (injini kadizili) iyacindezelwa, okwandisa ingcindezi kanye nokushisa.
3. Izinyathelo zamandla:
– Injini kaphethiloli: izinhlansi ze-spark plug ekupheleni kokucindezelwa, ukusabalala kwelangabi, ingcindezi iyakhuphuka, i-piston iyacindezelwa phansi.
– Injini yedizili: i-injector ifutha uphethiloli, kuba nokulibaziseka okufushane kokusha, bese kuba khona ukusha bese kusunduza i-piston.
4. Ukushaya komoya ophumayo: i-piston iyaphakama futhi, i-valve yomoya ophumayo iyavuleka, amagesi okushisa asele ayakhishwa.
Yilapho isikhathi sibaluleke khona: lapho i-spark plug ivutha noma lapho i-injector sprays inquma amandla, ukusebenza kahle, kanye nokukhishwa kwegesi.
5. Isilinganiso Sokuxubana Komoya Nophethiloli (AFR)
Enye yemiqondo ebaluleke kakhulu isilinganiso somoya-uphethiloli (i-AFR).
– Ezinjinini zikaphethiloli, ingxube yamakhemikhali ekahle (stoichiometric) ngokuvamile icishe ibe ngu-14,7:1 (umoya: uphethiloli) ngesisindo. Le ngxube ivumela i-catalytic converter ukuthi inciphise ngempumelelo ukukhishwa kwe-CO, HC, kanye ne-NOx.
– Ingxube ecebile kakhulu (uphethiloli owedlulele) ivame ukukhiqiza amandla aphezulu ngaphansi kwezimo ezithile, kodwa iyachitha futhi ukukhishwa kwe-CO/HC kuyanda.
– Ingxube engaqinile kakhulu (umoya oweqile) ingaba yingozi kakhulu ngaphansi kwezimo ezithile, kodwa ibeka engcupheni yokunciphisa amandla, ibangele amazinga okushisa aphezulu (ukwanda kwe-NOx), futhi ikhulise amathuba okuqhuma kabi uma idlulele kakhulu.
Ezinjinini zedizili, ukulawulwa kuvame ukuba ngaphezulu ngenani likaphethiloli ojovwe, kuyilapho umoya ugcwele kakhulu (uthambile). Ngenxa yalokhu, idizili yaziwa ngokusebenza kwayo kahle, kodwa ukulawula i-NOx kanye nezinhlayiya (umswakamo) kuyinselele.
6. Ukusha Okuvamile vs Ukusha Okungavamile
Ukusha okuvamile enjinini kaphethiloli kwenzeka njengoba ilangabi elilawulwayo lisakazeka lisuka endaweni yokuxhuma inhlansi kuyo yonke ingxube. Kodwa-ke, kunezimo ezingavamile, njenge:
1. Ukungqongqoza (ukuqhuma): kwenzeka lapho ingxube ivutha ngokuzenzekelayo kwenye indawo ngaphambi kokuba umjikelezo ojwayelekile womlilo uphele. Lokhu kubangela umsindo "wokuchofoza", ukwanda okungazelelwe kwezinga lokushisa kanye nokucindezela, futhi kungalimaza i-piston noma amasongo ngokuhamba kwesikhathi.
2. Ngaphambi kokushisa: ingxube iyavutha ngaphambi kokuba i-spark plug ivuthe, ngokuvamile ngenxa yezindawo ezishisayo njenge-carbon deposits, i-spark plug eshisa kakhulu, noma izingxenye ezishisa kakhulu.
3. Ukusha: ukusha kuyaphela noma akuphelele, okubangela ukuba injini ishabalale kabi, amandla ehle, ukusetshenziswa kwande, kanye nokukhishwa kwe-HC kwande.
Ezinjinini zedizili, izinkinga ezivamile zifaka phakathi ukushaqeka okulibazisekile, ukushaqeka kwedizili (ukushaqeka ngenxa yokushaqeka okude), intuthu eningi (emnyama/emhlophe), kanye nokudlidliza.
7. Izici Ezithinta Ukusebenza Kahle Kokushisa
Izici eziningana eziyinhloko ezinquma ukuthi ukusha kuhle noma kubi zifaka:
– Isilinganiso sokucindezela: uma amandla okusebenza kahle kokushisa ephezulu, kodwa kuphethiloli kunqunyelwe ingozi yokungqongqoza.
– Ikhwalithi ye-atomization kaphethiloli: i-injector enhle ikhiqiza amaconsi amancane ahlangana kalula futhi ashise kahle.
– Ukwakheka kwegumbi lokushiswa kwemimoya kanye nokushiswa kwemimoya: ukunyakaza komoya (ukujika/ukugoba) kusiza ukuxuba nokusheshisa ukushiswa kwemimoya.
– Isikhathi sokushisa/sokufaka: ukushesha kakhulu noma ukubambezeleka kakhulu kunganciphisa amandla futhi kwandise ukukhishwa kwegesi.
– Isimo se-spark plug (izinjini zikaphethiloli): igebe le-electrode, amadiphozithi kanye nezinga lokushisa le-spark plug kuthinta ikhwalithi ye-spark.
– Izinzwa kanye nezilawuli ze-ECU: izinjini zesimanje zisebenzisa i-O2/AFR, i-MAP/MAF, izinga lokushisa, izinzwa zokungqongqoza, nokuningi ukulawula ngokunembile ingxube nesikhathi.
8. Ukukhishwa Kwegesi Ephumayo Nobudlelwano Bayo Nokusha
Imikhiqizo eyinhloko yokushisa okuhle kakhulu yi-CO2 kanye ne-H2O. Kodwa-ke, ukushisa enjinini yangempela kukhiqiza okunye ukukhishwa kwegesi:
– I-CO (i-carbon monoxide): iyanda uma ingxube icebile kakhulu noma ukusha kungaphelele.
– I-HC (ama-hydrocarbon): ivela kuphethiloli ongashiswanga, ivame ukuvela ngesikhathi somlilo ongasebenzi kahle noma i-carburetion embi.
– I-NOx (i-nitrogen oxides): iyanda emazingeni okushisa aphezulu okushisa, okuvame ukuhlotshaniswa nezingxube ezithambile kanye nezikhathi ezithile.
– Izinhlayiya (PM/soot): zinamandla kudizili futhi zingavela nakuphethiloli ojova ngqo (GDI) uma ukulawula kungasebenzi kahle.
Yingakho izimoto zanamuhla zisebenzisa ama-catalytic converters, ama-EGR, ama-O2 sensor, kanti kudizili, i-DPF ne-SCR zengezwa ukunciphisa ukukhishwa kwegesi.
Isiphetho
Uhlelo oluyisisekelo lokusha ezinjinini zezimoto luhilela ukuguqula amandla kaphethiloli abe amandla ngokusebenzisa ukusabela kokusha okulawulwayo. Izinjini zikaphethiloli zisha ingxube nge-spark plug, kuyilapho izinjini zikadizili zisebenzisa ukushisa kokucindezelwa ukuze zisha uphethiloli ojoviwe. Ukusha okuphumelelayo kuthonywa yikhwalithi yengxube yomoya-kaphethiloli, isilinganiso sokucindezelwa, isikhathi sokusha/sokufaka, ukwakheka kwegumbi lokusha, kanye nokulawulwa kwe-elekthronikhi kwe-ECU. Ukusha okuhle kukhiqiza amandla afanele, ukusetshenziswa kukaphethiloli okusebenzayo, kanye nokukhishwa okuphansi kokukhishwa—kuyilapho ukusha okungavamile njengokungqongqoza kanye nomlilo ongalungile kungalimaza ukusebenza futhi kusheshise umonakalo wenjini. Ngokuqonda izisekelo, singenza kalula ukulungiswa, sixilonge izinkinga, futhi sikhethe izitayela zikaphethiloli nokushayela ezisekela ukusebenza kwenjini.
Uma uthanda, ngingaqhubeka nezihloko ezincane zobuchwepheshe ezifana nalezi: indima yezinzwa ze-O2 kanye nokulawulwa kukaphethiloli okuvaliwe, izibalo ze-AFR kanye ne-stoichiometry, noma umehluko ekushiseni ku-EFI vs GDI vs carburetors.
