Saboda batun yana da sarkakiya, bari mu fara bayyana a taƙaice ra'ayin matsi don fahimtar dalilin da yasa injin matsawa na Nissan VC-T ya zama na ban mamaki? Don haka zan yi ƙoƙari in sauƙaƙa, a cikin haɗarin yin kuskure - idan hakan ta faru koyaushe kuna iya shiga Facebook ɗin mu ku bar mana sharhi.
Ƙimar me?
Matsakaicin matsawa shine adadin lokutan da aka matsa ƙarar da aka bayar a cikin silinda. Misali mai amfani: injin silinda mai girman lita 1.0 tare da rabon 10:1 yana da silinda 250 cm³ wanda, a saman matattu cibiyar, damfara cakuda zuwa ƙarar kawai 25 cm³ - wato, zuwa kashi ɗaya bisa goma na ƙarar sa ( 10: 1). Ana iya ganin hadadden sigar bayanin rabon matsawa anan.Kuma me yasa wannan yake da mahimmanci haka?
Domin yawan matsewar injin injin, mafi girman ingancinsa. Mafi girman matsawar injin, saurin haɓakar iskar gas ɗin da ke haifar da fashewar kuma sakamakon haka saurin saukar piston da sandar haɗi, sabili da haka saurin ƙaura na crankshaft - a ƙarshe yana haifar da ƙarin motsi da aka watsa zuwa abin hawa. ƙafafunni. Shi ya sa motocin wasanni ke da mafi girman matsi - alal misali, injin V10 na Audi R8 yana matsawa sau 12.7 girma.
To me yasa duk motoci ba su da babban matsi?
Don dalilai guda biyu: dalili na farko shi ne cakuda ya riga ya tashi kuma dalili na biyu shi ne cewa yana da tsada don yin inji mai nauyin matsi. Amma bari mu fara zuwa dalili na farko. Yayin da rabon matsawa ya karu, haka ma zafin iska da man gas a cikin dakin konewa kuma wannan karuwar zafin na iya haifar da kunnawa kafin fistan ya kai ga babban matattu. Sunan wannan al'amari shine pre-detonation kuma saboda wannan tasirin ne aka tilasta wa samfuran motoci samar da injuna tare da ƙimar matsi na mazan jiya, tare da kunnawa da taswirar allura da aka ƙera don kare injin daga wannan al'amari a cikin ƙimar mafi girman inganci.A daya hannun, samar da injuna tare da babban matsawa rabo shi ma tsada (ga brands sabili da haka ga abokan ciniki…). Domin kauce wa fashewar injuna masu yawan matsewa, dole ne masu sana'a su yi amfani da abubuwan da suka fi kyau da kuma juriya waɗanda ke watsar da zafin da ke cikin injin ɗin yadda ya kamata.
Nissan ya samo (a ƙarshe!) mafita
A cikin shekaru 25 da suka gabata kamfanoni da yawa sun yi ƙoƙari ba su yi nasara ba don shawo kan iyakokin injuna zuwa wannan matakin. Saab yana ɗaya daga cikin samfuran da suka zo kusa, har ma da gabatar da injin juyin juya hali wanda, godiya ga motsi na gefen injin, ya sami damar haɓaka ko rage ƙarfin ɗakin konewa. don haka rabon matsawa. Matsala? Tsarin yana da gazawar dogaro kuma bai taɓa sanya shi cikin samarwa ba. Abin farin ciki…
Alamar farko don samo mafita shine, kamar yadda muka ce, Nissan. Alamar da za ta gabatar da injin matsi na farko a duniya a watan Satumba a Nunin Mota na Paris. Yana da injin Turbo 2.0 tare da 274 hp da 390 Nm na matsakaicin karfin juyi. Za a fara harba wannan injin ne kawai a cikin Amurka, wanda zai maye gurbin injin 3.5 V6 wanda a halin yanzu ke ba da samfuran Infiniti (Nissan's premium model division).
Ta yaya Nissan ta cimma hakan?
Maita ne. Ina wasa… injiniyanci ne tsantsa. A cikin injuna na al'ada an haɗa sandunan haɗin kai (waɗannan hannun da ke “kama” piston) suna haɗe kai tsaye zuwa crankshaft, a cikin injin Nissan VC-T wannan ba ya faruwa. Kamar yadda kuke gani a hoton da ke kasa:
A cikin wannan injin Nissan na juyin juya hali an rage tsawon babban sandar haɗin haɗin gwiwa kuma an haɗa shi zuwa matsakaicin lever wanda ke jujjuya shi zuwa crankshaft kuma an haɗa shi da sandar haɗi mai motsi ta biyu a gaban sandar haɗi wanda ya bambanta girman motsin piston. Lokacin da na'ura mai sarrafa injin ya ƙayyade cewa yana da mahimmanci don ƙarawa ko rage ma'aunin matsawa, mai kunnawa yana canza kusurwar madaidaicin lever, yana ɗagawa ko rage sandar haɗi don haka ya bambanta da matsawa tsakanin 8: 1 da 14: 1. Don haka, injin Nissan yana kula da haɗa mafi kyawun duniyoyin biyu: matsakaicin inganci a ƙananan rpm da ƙarin iko a babban rpm, guje wa tasirin pre-detonation.
Wannan bambance-bambance a cikin rabon matsi na injin yana yiwuwa kawai da inganci kuma a cikin kowane zangon rpm, godiya ga ɗimbin na'urori masu auna firikwensin da suka bazu cikin injin. Wadannan suna aika dubban daruruwan bayanai a cikin dakika daya zuwa ECU a cikin ainihin lokaci (zazzabi na iska, ɗakin konewa, sha, turbo, adadin iskar oxygen a cikin cakuda, da dai sauransu), yana ba da damar canza yanayin matsawa daidai da bukatun. na abin hawa. Haka kuma wannan injin an sanye shi da na’ura mai canza yanayin lokaci don yin kwatankwacin zagayowar Atkinson, inda bawul ɗin da ke ɗauke da shi ya daɗe a buɗe don ba da damar iska ta fita ta wurinsu, don haka yana rage juriyar injin ɗin a lokacin matsawa.
Wadanda suka yi ta sanar da ƙarshen injin konewa na ciki dole ne su koma don "ajiye guitar a cikin jaka" . Injunan konewa na cikin "tsohuwar" sun riga sun wuce shekaru 120 kuma da alama suna nan don zama. Abin jira a gani shine ko wannan maganin zai zama abin dogaro.
Dan karin tarihi?
Nazari na farko a kan illolin matsawa akan aikin sake zagayowar aikin injunan konewa na ciki ya kasance tun 1920, lokacin da injiniyan Biritaniya Harry Ricardo ya jagoranci Sashen Ci gaban Aeronautical na Royal Air Force (RAF). Ɗaya daga cikin muhimman ayyukansa shine neman mafita ga yawan man da jirgin na RAF ke amfani da shi da kuma sakamakon gajeren zangon tashi. Don nazarin abubuwan da ke haifar da wannan matsala da mafita, Harry Ricardo ya kirkiro injin gwaji tare da matsawa mai canzawa inda ya gano (cikin wasu abubuwa) cewa wasu man fetur sun fi tsayayya da fashewa. Wannan binciken ya ƙare a cikin ƙirƙirar tsarin ƙimar octane na man fetur na farko.
Godiya ga waɗannan karatun ne, a karon farko, an ƙaddamar da cewa mafi girman ma'aunin matsawa sun fi dacewa kuma suna buƙatar ƙarancin man fetur don samar da makamashi iri ɗaya. Daga wannan lokacin ne manyan injinan da ke da lita 25 na karfin cubic - waɗanda muka sani daga jiragen yakin duniya na farko - sun fara ba da hanya ga ƙananan raka'a masu inganci. Tafiya ta Transatlantic ta zama gaskiya kuma an rage iyakokin dabara yayin yaƙin (saboda yawan injuna).
