Inombolo octane uphethiloli

Gasoline - uketshezi oluvuthayo abangenalo umbala, noma ephethe tinge kancane aphuzi (uma kungekho izithasiselo ekhethekile). Ukuze uthuthukise properties ukusebenza kukaphethiloli motor elisetshenziswa yangaphakathi omlilo izinjini, abakhiqizi ozama ukwandisa isibalo octane uphethiloli. Ukuze wenze lokhu, engeza izingxenye ohambelana kuwo. Uma amandla omlilo isici umsindo ezwakalayo metal ezivezwa wave detonation okubangelwa kuveza eziningi ze-cylinder yayo odongeni, nekusebenta motor kuyehla, ngaphezu kwalokho, it is yanda bafake.

Kulokhu sithi abampofu fuel izinga, njengoba inombolo octane uphansi. Detonation injini fuel ukuzinza, isb ikhono simelane self-ukuthungela ngenxa yokucinana kule amasilinda kanye yokusebenza injini ephawula lesi sibalo. Ngokwezinombolo kuba ingxenyenamba ivolumu isooctane (elinye igama: 2,2,4-trimethylpentane) ingxube ezimbili ingxenye equkethe futhi n-heptane. inhlanganisela enjalo ngokuphathelene antiknock yayo ngaphansi kwezimo ukuhlolwa ejwayelekile ukhiqiza umphumela okulingana fuel uphenyo.

Isooctane - branched uchungechunge elihlale hydrocarbon C8H18. Kuyinto ngenxa impahla yayo, kunzima oxidize ngisho at high zlib isilinganiso, ngakho ubizwa evamile wamukela engqongqoza ukumelana amayunithi 100. N-heptane e motor iziphatha ngendlela ehlukile: Nokho, ngisho nalapho ongaphakeme kokucindezelwa okungu kuhambisana inqubo amandla omlilo detonation Empeleni, lokhu kulinganisela ethathwa njengolibo amayunithi 0 ngenxa yalo. Kulezo zimo lapho uphethiloli inombolo octane ngenhla 100, ngoba nokuhlola izinga layo isikali isicelo Izingxube okunemibandela yalo, lapho ingxenye main - isooctane - tetraethyl ungeze imithamo ahlukahlukene.

Ngakho-ke, kungashiwo wagomela ukuthi lesi sibalo isici eziphawuleka kakhulu motor nophethiloli. Ibonisa kangakanani likaphethiloli olumelana detonation, lowo ngumlilo okungahleliwe kule amasilinda injini. fuel ukuqhuma ematfuba yangaphakathi omlilo injini kuyoba abasengozini kakhulu uma le izinga liphezulu. Uma inombolo octane uphethiloli okuhambelana amayunithi 95, ke detonates ingxube ehlanganisa 95% 2,2,4-trimethylpentane futhi 5% heptane evamile. Ngemva ukwelashwa esiyinhloko uwoyela umkhiqizo ngokuthi naphtha, lesi silinganiso isici akuvamile idlula amayunithi 70. Ngakho-ke, ukwenza ngcono ikhwalithi ongaphakeme grade uphethiloli isetshenziswe kuphela ezihlanganisiwe (ukuxuba imikhiqizo high-octane), kodwa futhi antidetonators yaphathwa isamba ukufika kuma-0.3%.

izinga Okokhelekayo kuxhomeke kakhulu ukwakheka amaminerali, kusukela kulo etholwe zihlukaniswa noma ziphuzo zazihluzwa, - uwoyela. Kubalulekile nezinto ezifana viscosity, ukwakheka wamaqhuzu, khona-sulphur compounds kanye paraffins, futhi okuqukethwe amanzi oncibilikile therein. Nokho, lezi zici cishe nomthelela ukucutshungulwa izici kanye nokuzikhethela ubuchwepheshe. Ikhwalithi uphethiloli, isb inombolo octane yayo value, inquma hydrocarbon yokwakheka uwoyela, bese indlela izocubungulwa yayo, nakho kuncike kangakanani nophethiloli uyindlala isooctane, n-heptane, ezinuka kamnandi, kanjalonjalo.

Thuthukisa antiknock izakhiwo uphethiloli yawo Aromatics. Okuqukethwe eliphezulu benzene, ngokuyinhloko kuthinta isimo imvelo deku benzopyrene (umdlavuza). Amazinga aphakeme okusezingeni eliphezulu ukubila Aromatics ikhuthaza umule kumiswa ekamelweni amandla omlilo futhi valve injini. Konke lokhu elilulaza zemisebenzi ezifana injini ukusebenza kanye nokusebenza kahle, ezemvelo kanye izici kwezomnotho umsebenzi walo. Kuthiwa isisi kwakheka egumbini amandla omlilo kubangela umnikazi imoto ukhethe injini fuel ukuze isibalo octane we uphethiloli yayiphezulu. Kungenjalo, amandla is kakhulu ziyancipha noma injini isebenza nge detonation.