Ndondomeko ya EGR

Dongosolo la Exhaust Gas Recirculation (EGR) lidapangidwa kuti lithandizire kuwongolera chilengedwe cha injini yamagalimoto. Kugwiritsa ntchito kwake kumatha kuchepetsa kuchuluka kwa ma nitrogen oxide mumipweya yotulutsa mpweya. Zotsirizirazi sizimachotsedwa mokwanira ndi otembenuza othandizira ndipo, popeza ndizomwe zimakhala zoopsa kwambiri pakupanga mpweya wotulutsa mpweya, kugwiritsa ntchito njira zowonjezera ndi matekinoloje kumafunika.

Momwe dongosololi limagwirira ntchito

EGR ndi chidule cha mawu achingerezi akuti "Exhaust Gas Recirculation", omwe amatanthawuza "kutulutsa mpweya wotulutsa mpweya". Ntchito yaikulu ya dongosolo loterolo ndikupatutsa gawo la mpweya kuchokera ku utsi wochuluka kupita kumalo ochuluka. Mapangidwe a nitrogen oxides amagwirizana mwachindunji ndi kutentha kwa chipinda choyaka cha injini. Pamene mpweya wotulutsa mpweya wochokera ku dongosolo lotopetsa umalowa m'dongosolo lakumwa, mpweya wa okosijeni, womwe umakhala ngati chothandizira panthawi ya kuyaka, umachepa. Zotsatira zake, kutentha kwa chipinda choyaka moto kumachepa ndipo kuchuluka kwa mapangidwe a nitrogen oxide kumachepa.

Dongosolo la EGR limagwiritsidwa ntchito pamainjini a dizilo ndi mafuta. Kupatulapo kokha ndi magalimoto amafuta a turbocharged, pomwe kugwiritsa ntchito ukadaulo wa recirculation sikukwanira chifukwa chazomwe zimapangidwira injini. Nthawi zambiri, ukadaulo wa EGR ungachepetse kuchuluka kwa nitrogen oxide mpaka 50%. Kuphatikiza apo, kuthekera kwa detonation kumachepetsedwa, kugwiritsa ntchito mafuta kumakhala kokwera mtengo (pafupifupi 3%), ndipo magalimoto a dizilo amadziwika ndi kuchepa kwa kuchuluka kwa mwaye mumipweya yotulutsa mpweya.

Mtima wa dongosolo la EGR ndi valavu yobwezeretsanso, yomwe imayendetsa kutuluka kwa mpweya wotulutsa mpweya muzinthu zambiri. Zimagwira ntchito pa kutentha kwakukulu ndipo zimakhala ndi katundu wambiri. Kuchepetsa kutentha kokakamiza kungapangidwe, zomwe zimafuna radiator (zozizira) zomwe zimayikidwa pakati pa makina otulutsa mpweya ndi valve. Ndi mbali ya dongosolo lonse kuzirala galimoto.

Mu injini za dizilo, valavu ya EGR imatsegulidwa popanda ntchito. Pankhaniyi, mpweya wotulutsa mpweya umapanga 50% ya mpweya wolowa m'zipinda zoyaka. Pamene katundu akuwonjezeka, valavu imatseka pang'onopang'ono. Kwa injini ya petulo, makina ozungulira nthawi zambiri amagwira ntchito pa liwiro lapakati komanso lotsika la injini ndipo amapereka mpaka 10% ya mpweya wotulutsa mpweya wokwanira.

Mavavu a EGR ndi chiyani

Pakalipano, pali mitundu itatu ya ma valve otulutsa mpweya, omwe amasiyana ndi mtundu wa actuator:

• Mpweya. Chosavuta, koma chachikale cha actuator chamagetsi otulutsa mpweya. M'malo mwake, zotsatira zake pa valavu zimachitika ndi vacuum mu kuchuluka kwa magalimoto.
• Electropneumatic. Valavu ya Pneumatic EGR imayang'aniridwa ndi valve solenoid, yomwe imagwira ntchito kuchokera ku injini ya ECU yochokera ku data kuchokera ku masensa angapo (kutulutsa mpweya wa mpweya ndi kutentha, malo a valve, kuthamanga kwa mpweya ndi kutentha kozizira). Imagwirizanitsa ndikuchotsa gwero la vacuum ndikupanga malo awiri okha a valve ya EGR. Komanso, vacuum mu dongosolo wotero akhoza kupangidwa ndi osiyana vacuum mpope.
• Pakompyuta. Valavu yamtunduwu imayendetsedwa mwachindunji ndi injini yagalimoto ECU. Ili ndi malo atatu owongolera mpweya wabwino. Malo a valavu yamagetsi ya EGR amasinthidwa ndi maginito omwe amatsegula ndi kutseka muzosakaniza zosiyanasiyana. Dongosololi siligwiritsa ntchito vacuum.

Mitundu ya EGR mu injini ya dizilo

Injini ya dizilo imagwiritsa ntchito mitundu yosiyanasiyana yamagetsi otulutsa mpweya, kuphimba komwe kumatsimikiziridwa ndi miyezo yachilengedwe yagalimoto. Pano pali atatu mwa iwo:

• Kuthamanga kwakukulu (kumagwirizana ndi Euro 4). Valve yobwerezabwereza imagwirizanitsa doko lotulutsa mpweya, lomwe limayikidwa kutsogolo kwa turbocharger, molunjika ku manifold ambiri. Derali limagwiritsa ntchito ma electro-pneumatic drive. Pamene throttle yatsekedwa, kupanikizika muzolowera kumachepa, zomwe zimapangitsa kuti vacuum iwonongeke. Izi zimapanga kuchuluka kwa mpweya wotulutsa mpweya. Kumbali ina, mphamvu yowonjezereka imachepetsedwa chifukwa mpweya wocheperako umalowetsedwa mu turbine. Pakutseguka kwakukulu, makina otulutsa mpweya sagwira ntchito.
• Kuthamanga kochepa (kumagwirizana ndi Euro 5). Muchiwembu ichi, valavu imagwirizanitsidwa ndi dongosolo lotulutsa mpweya m'deralo pakati pa fyuluta ya particulate ndi muffler, komanso mu dongosolo lodyera pamaso pa turbocharger. Chifukwa cha mankhwalawa, kutentha kwa mpweya wotulutsa mpweya kumachepetsedwa, ndipo amatsukidwa ndi zonyansa za mwaye. Pankhaniyi, poyerekeza ndi chiwembu chothamanga kwambiri, kupanikizika kumachitidwa mokwanira, chifukwa mpweya wonse umadutsa mu turbine.
• Zophatikizidwa (zofanana ndi Euro 6). Ndi kuphatikiza kwa maulendo apamwamba ndi otsika kwambiri, iliyonse ili ndi ma valve ake obwereza. Mumayendedwe abwinobwino, derali limagwira ntchito panjira yotsika kwambiri, ndipo njira yolumikiziranso kuthamanga kwambiri imalumikizidwa pomwe katundu ukuwonjezeka.

Pafupifupi, valavu yotulutsa mpweya wotulutsa mpweya imatha mpaka 100 km, pambuyo pake imatha kutseka ndikulephera. Nthawi zambiri, madalaivala omwe sadziwa kuti recirculation system ndi chiyani amangowachotsa kwathunthu.