Yintoni inkqubo adiabatic?

Ukuze kube nokwakhiwa injini nobushushu, nto leyo ukwenza umsebenzi ngokusebenzisa nobushushu, kufuneka ukudala iimeko ezithile. Kuqala kwinto zonke, i-injini ubushushu ukuba zisebenze kwindlela elibujikele, apho inani iinkqubo ezilandelelanayo thermodynamic ukwenza i loop. kuyasebenza Isiphumo igesi lomjikelo list itankana kunye piston eziphathekayo,. Kodwa omnye umjikelo ngomatshini ibhetshi kancinane, kufuneka iterate ngokuphindaphindiweyo kangangexesha elithile. Umsebenzi iyonke wenziwe ngexesha kwangaphambili eneneni lahlulwe ixesha unika enye ingcamango ebalulekileyo - amandla.

Phakathi kwinkulungwane XIX, le iinjini ubushushu yokuqala zadalwa. Zezona umsebenzi, kodwa bachitha imali engakumbi ubushushu eveliswe ukutshiswa amafutha. Kungelo xesha zesayensi yeengcingane esikucelayo, "njani umsebenzi igesi i injini ubushushu? Ungayifumana njani i-msebenzi kunye ubuncinane yesibaso? "

Ukuze enze uhlalutyo imisebenzi igesi , oko kwakufuneka ukuqalisa inkqubo iphela iinkcazelo kunye magama. Wokuhlangana zonke nomiselo waza wadala ummandla uphando yonke, ebizwa ngokuba "Engineering obizwa". Xa obizwa, samkelwa kweenkolelo ngeenkolelo, imke izigqibo eziphambili. Izixhobo zomzimba - igesi zexeshana (hayi ekhoyo kwindalo) apho kungenziwa zixinaniswe ku zero umthamo wakhe iimolekyuli musa basebenzisane. Kwimeko-bume yendalo abakho kuphela iigesi yokwenene, okuye iipropati kakuhle echazwe enzima ukusuka igesi efanelekileyo.

Ukujonga umfuziselo Dynamics kulwelo ukusebenza, kuye ezicetyiswayo imithetho obizwa, echaza iinkqubo zolawulo ezisisiseko thermodynamic ezifana:

• inkqubo isochoric - yomsebenzi eyenziwa ngaphandle kokutshintsha umthamo kulwelo ukusebenza. Iimeko inkqubo isochoric, v = nengngqi;
• inkqubo isobaric - yomsebenzi eyenziwa ngaphandle kokutshintsha uxinzelelo kwi kulwelo ukusebenza. Iimeko inkqubo isobaric, P = nengngqi;
• isothermal (isothermal) inkqubo - inkqubo leyo yenzelwa lo gama kugcinwe iqondo lobushushu kwinqanaba kwangaphambili. Iimeko inkqubo isothermal, T = nengngqi;
• inkqubo adiabatic (adiabatic, ngoko ubizwa ngokuba Engineering Thermal mihla) - inkqubo, lwenziwa kwisithuba ngaphandle ngokutshintshiselana ubushushu kunye nokusingqongileyo. Imiqathango yenkqubo adiabatic, q = 0;
• inkqubo polytropic - yinkqubo ngokubanzi elichaza zonke iinkqubo thermodynamic okhankanywe ngentla, kwakunye namanye onke amathuba ukuze kuzaliseka itankana kunye piston eshukumayo.

Ngexesha ukudalwa iinjini ubushushu yokuqala agqogqa umjikelo apho ukufumana ukusebenza liphezulu (ukungavumelani kwe yokusebenza). Sadi Carnot, ukuhlolisisa iseti iinkqubo thermodynamic, kwi benze waya kuphuhliso kumjikelo, ogama emva kwakhe - umjikelo Carnot. It ngokulandelana wenza isothermal, ngoko ke inkqubo ucinezelo adiabatic. Kulwelo ukusebenza emva kokuba ukuphunyezwa kwale nkqubo sele uqhelane amandla lwangaphakathi, kodwa umjikelo kungekagqitywa, ngoko ulwelo ukusebenza uyandiswa ze yenza inkqubo ukwanda isothermal. Ukugqiba umjikelo uze ubuyele sokuqala ukusebenza ulwelo parameters, inkqubo ukwanda adiabatic luyenziwa.

Carnot wabonisa ukuba ukusebenza kumjikelo yayo ufikelela ubuninzi, kwaye kuxhomekeke kuphela amaqondo obushushu kwezi isotherms ezimbini. Uphakamile umahluko phakathi kwabo, ukusebenza ngokukwanjalo eliphezulu thermal. Imizamo ukuba ukudala injini ubushushu komjikelo Carnot kwaye ziwe phantsi. Lo mjikelo Ngumnqweno awukwazi ukwenziwa. Kodwa wazibonakalisa umgaqo engundoqo yomthetho yesibini obizwa, malunga akunakwenzeka ukufumana umsebenzi, lingana ne ukuya iindleko zamandla thermal. inani nkcazelo laliqulunqwe umthetho yesibini (umthetho) Umthetho obizwa, njengako apho Rudolf Clausius laqalisa ingqikelelo entropy. Isiphelo eziphambili kuphando - entropy iya isanda, nto leyo ekhokelela thermal "ukufa".

Eyona mpumelelo ibalulekileyo yaba Clausius nokuqonda inkqubo adiabatic kuphumezo yalo kulwelo ukusebenza entropy akatshintshi. Ngoko ke, inkqubo adiabatic Clausius - na s = nengngqi. Apha s - yi entropy, enika elinye igama le nkqubo yenziwe ngaphandle ekukhutshweni okanye ukususa ubushushu, - inkqubo isentropic. Izazinzulu ufuna umjikelo injini ubushushu ezinjalo, naphi na apho kwakukho ukwanda entropy. Kodwa ke, ngelishwa, koko ayikwazanga ukudala. Ngoko ibonakala ukuba injini ubushushu awubunjwa konke konke.

Kodwa asingabo bonke abaphandi ukuba yakhiwe lokuhle. Bona lalifuna lemijikelo kanye ukuba koomatshini thermal. Ngenxa uphendlo lwabo uNikolaus Agasti Otto yayo injini Umjikelo ubushushu, ngoku athe aphumeza kwinjini iyasebenza ipetroli. Apha, inkqubo eyenziwa ucinezelo adiabatic lomzimba yokusebenza supply nobushushu isochoric (ukutsha kwamafutha yalamanxila rhoqo), ngoko kukho ukwanda adiabatic (umsebenzi owenziwe eliphakathi ukusebenza kwinkqubo ukwandisa umthamo wayo), kunye nokususwa ubushushu isochoric. I-injini yokuvutha kwangaphakathi wokuqala yomjikelo Otto lasetyenziswa irhasi amafutha ezinokutsha. Kamva oko yasungulwa carburetors eziye benzovozdushnoy ukudala umxube emoyeni umphunga ipetroli nokondla ukuba lombhobho injini.

In Otto umxube amafutha mjikelo zixinaniswe, ngoko ke isixa ucinezelo kwayo omncinane - fuel umxube has ukuthambekela zicace (enokudubula uxinzelelo ezibalulekileyo kunye namaqondo). Ngoko ke, lo msebenzi yinkqubo ucinezelo adiabatic liphantsi kakhulu. Apha ukwazisa omnye magama: umlinganiselo ucinezelo - umlinganiselo ngumthamo opheleleyo ukuya umthamo ucinezelo.

Ukufumana iindlela ukwandisa ukusebenza amafutha lwamandla yaqhubeka. Ukusebenza okunyukileyo kubonakala ekwandiseni ratio ucinezelo. Rudolf Diesel iphuhlise kumjikelo apho ubonelelo ubushushu oluqhutywa phaya njalo (kwinkqubo isobaric). kumjikelo yaba sisiseko iinjini usebenzisa amafutha emoto ayekwi (eyaziwa ngokuba diesel). Kumjikelo umxube amafutha Diesel ayenziwanga zixinaniswe, kunye nomoya. Ngako oko, bathi ukuba umsebenzi lwenziwa kwinkqubo adiabatic. Iqondo lobushushu kunye noxinzelelo ekupheleni ucinezelo eziphakamileyo, ngokunjalo kuya kuthi, isitofu amafutha amanzi esatsiba yenziwa. Idityaniswe umoya oshushu ukwenza umxube enokutsha. Utshisa, oku kwandisa amandla lwangaphakathi kulwelo ukusebenza. igesi Olunye ngu ukwandiswa adiabatic kukuthi, ayenza stroke ukusebenza.

Ukuzama ukuphumeza umjikelo Diesel iinjini ubushushu aluphumelelanga, umjikelo ngoko Gustav Trinkler yamathuba emisebenzi edibene Trinklera. Kwaye sebenzisa it kwinjini namhlanje idizili. Kumjikelo yobushushu ezinikwa yi Trinklera isochore, uze emva koko phezu isobars. Kuphela emva kokuba oku kwenziwe inkqubo adiabatic yokuba ukwandiswa kulwelo ukusebenza.

Ngu mfanekiso ne iinjini piston ubushushu kunye nomsebenzi turbine. Kodwa inkqubo yazo kukuhanjiswa ubushushu ekupheleni ukwanda luncedo adiabatic yalerhasi lwenziwa yi isobars. On moya, injini yerhasi, kunye nenkqubo turboprop adiabatic kwenzeka kabini ngexesha ucinezelo kunye nokwandiswa.

Ukuzithethelela zonke iingqiqo esisiseko yenkqubo adiabatic ziye ezicetywayo ifomula zokuhlala. Kukho livela ixabiso ebalulekileyo, kuthiwa index adiabatic. ixabiso layo kuba irhasi diatomic (oksijini nitrogen - zezona iigesi diatomic ziphambili zikhoyo emoyeni) ilingana no 1.4. Ukubala index adiabatic esetyenzisiweyo uneempawu ezimbini umdla, oko kukuthi, izakhono ubushushu isobaric kwaye isochoric ye kulwelo ukusebenza. Umlinganiselo ye K = CP / CV - i index adiabatic.

Kutheni usebenzise inkqubo adiabatic kwimijikelo yeengcingane iinjini ubushushu? Eneneni enze inkqubo polytropic, kodwa ngenxa yokuba kwenzeke ngesantya esiphezulu, ukuba selikho, yamkeleka ukuba iqalise ukungabikho kunaniselwano ubushushu kunye nokusingqongileyo.

90% lombane eveliswa zizityalo ngamandla thermal. Kuzo kulwelo ukusebenza wasebenzisa umphunga. Oku iveliswa xa abilayo. Ukunyusa ukusebenza umthamo umphunga, oko utshisayo. Emva koko, uxinzelelo oluphezulu zomphunga esibaselwe inikezelwa kweinjini zomphunga. Kwakhona ukwenzeka adiabatic nokwandiswa inkqubo umphunga. Ephendulwa saphule ukuziqengqa, ke idluliselwe wokuphehla umbane. Loo nto, ovelisa umbane kwabayityayo. turbines umphunga asebenza ngomjikelo Rankine. Ngokunqwenelekayo ukusebenza kukwanxulunyaniswa ukwanda kwamaqondo obushushu kunye noxinzelelo umphunga.

Njengoko kubonakala ngentla apha, inkqubo adiabatic kuxhaphakile kakhulu kwimveliso amandla mechanical kunye zombane.