Isiokwu gbasara okirikiri injin Carnot
Iji chọpụta otu esi eme ka injin okpomọkụ dịkwuo mma, otu ọkà mmụta sayensị France aha ya bụ Sadi Carnot (1796-1832) mụrụ injin okpomọkụ zuru oke n'usoro ihe ọmụmụ na 1824. N'oge ahụ, e mebeghị iwu mbụ nke thermodynamics, ọ bụghịkwa iwu nke abụọ nke thermodynamics. E mebeghị iwu mbụ n'ihi na ndị ọkà mmụta sayensị amaghị na okpomọkụ bụ ike. Mgbe Joule na ndị enyi ya mere nnwale na 1830s, ndị ọkà mmụta sayensị maara naanị na okpomọkụ bụ ike a na-ebufe n'ihi ọdịiche okpomọkụ. Ya mere, e mepụtara iwu mbụ nke thermodynamics mgbe 1830 gasịrị. Sadi Carnot amụọla injin okpomọkụ zuru oke n'usoro ihe ọmụmụ na 1824. Nnyocha o mere bụ n'ezie ịbawanye arụmọrụ nke injin steam nke e ji eme ihe n'oge ahụ. Ọtụtụ injin steam n'oge ahụ adịghị arụ ọrụ nke ọma.
A na-akpọ okirikiri dị na injin okpomọkụ zuru oke, nke Sadi Carnot mepụtara, okirikiri Carnot. Tupu anyị enyocha okirikiri Carnot, ọ bara uru ịghọta usoro ndị a na-apụghị ịgbanwe agbanwe. Usoro mgbanwe na mbufe ike ọ bụla na-eme n'onwe ya na-abụkarị nke a na-apụghị ịgbanwe agbanwe. Dịka ọmụmaatụ, ọ bụrụ na anyị tee aka anyị ọnụ, ha na-adị ọkụ. N'okwu a, a na-emepụta okpomọkụ site na ọrụ anyị na-arụ. Usoro a enweghị ike ịgbanwe agbanwe. Okpomọkụ emepụtara enweghị ike ịrụ ọrụ n'onwe ya site n'ịcha aka anyị ọnụ. Ebumnuche nke injin okpomọkụ bụ ịgbanwe usoro a n'otu akụkụ, ebe enwere ike iji okpomọkụ rụọ ọrụ na arụmọrụ kachasị elu. Ka injin okpomọkụ wee nweta arụmọrụ kachasị elu, anyị ga-ezere usoro niile a na-apụghị ịgbanwe agbanwe. Nbufe okpomọkụ na-emekarị na-enweghị ike ịgbanwe agbanwe, ya mere a na-eme mgbalị iji gbochie mbufe okpomọkụ.
Mgbe injin ahụ na-ewe okpomọkụ QH n'ebe nwere oke okpomọkụ (T)H), ihe na-arụ ọrụ n'ime igwe ahụ ga-adịkwa na okpomọkụ THN'otu aka ahụ, ọ bụrụ na injin ahụ ewepụ okpomọkụ QL n'ebe nwere obere okpomọkụ (T)L), ihe na-arụ ọrụ n'ime igwe ahụ ga-adịkwa na okpomọkụ TLYa mere, usoro ọ bụla nke gụnyere nnyefe okpomọkụ ga-abụrịrị isothermal (otu okpomọkụ ahụ). N'aka nke ọzọ, ọ bụrụ na okpomọkụ nke ihe na-arụ ọrụ na injin ahụ dị n'etiti TH na TL, agaghị enwe mbufe okpomọkụ n'etiti igwe na ebe nwere okpomọkụ TH (onye na-enye okpomọkụ) na ebe nwere okpomọkụ TL (ikpofu). Ka okpomọkụ ghara ịpụ apụ, a ga-emerịrị usoro ahụ n'ụzọ nkịtị.
Usoro Carnot nwere usoro isothermal abụọ a na-agbanwe agbanwe na usoro adiabatic abụọ a na-agbanwe agbanwe.
Foto dị n'aka nri na-egosi okirikiri Carnot maka gas zuru oke. Na mbụ, a na-amịkọrọ okpomọkụ n'oge mgbasawanye isothermal (a-b). N'oge mgbasawanye isothermal, a na-anọgide na-enwe okpomọkụ nke gas dị na silinda ahụ.
Na-esote, gas ahụ na-agbasa n'ụzọ dị iche iche ka okpomọkụ ya wee daa site na T H ruo T L (b-c). T H = okpomọkụ dị elu (Okpomọkụ dị elu), T L = okpomọkụ dị ala (Okpomọkụ dị ala). N'oge mgbasa adiabatic, okpomọkụ ọ bụla na-abanye ma ọ bụ na-apụ na silinda. Mgbe nke ahụ gasịrị, a na-agbakọ gas ahụ n'ụzọ dị iche iche (c-d). N'oge nrụgide isothermal, a na-anọgide na-enwe okpomọkụ gas ahụ. Na-esote, a na-agbakọ gas ahụ n'ụzọ dị iche iche (d-a). N'ihi na a na-agbakọ ya n'ụzọ dị iche iche, okpomọkụ gas ahụ na-abawanye. Okpomọkụ gas na-abawanye nke na nrụgide gas na-abawanyekwa. Usoro niile dị na okirikiri Carnot na-agbanwe agbanwe.
N'oge mgbasawanye na mkpakọ nke isothermal, a na-eme ka okpomọkụ gas dịgide. Ebumnuche bụ izere ọdịiche okpomọkụ. Ọdịiche okpomọkụ nwere ike ibute mbufe okpomọkụ (usoro a na-apụghị ịgbanwe agbanwe). Ka usoro isothermal wee mee (ịnọgide na-eme ka okpomọkụ gas dịgide), a ga-agbasa ma ọ bụ kpaa gas ahụ nwayọ nwayọ. N'eziokwu, mgbasawanye ma ọ bụ mkpakọ gas na-eme ngwa ngwa. Nke a bụ n'ihi ọgba aghara (cheta isiokwu nke mmiri mmiri), esemokwu, viscosity, wdg. N'ihi ya, usoro isothermal zuru oke agaghị adị. Kama nke ahụ, mgbasawanye adiabatic na mkpakọ na-eme ngwa ngwa.
Ebumnuche ya bụ igbochi okpomọkụ ịbanye ma ọ bụ ịpụ na silinda. Nsogbu, viscosity, na ihe ndị ọzọ na-egbochi mgbasa na mkpakọ zuru oke nke adiabatic. Ọ dị mkpa ịmara na injin Carnot bụ naanị echiche; ọ dịghị adị na ndụ anyị kwa ụbọchị. Ọ bụ ezie na echiche, injin Carnot na-enye aka nke ukwuu na mmepe nke thermodynamics. Ma ọ dịkarịa ala, anyị nwere ike ịchọpụta usoro ọ bụla a na-apụghị ịgbanwe agbanwe nke nwere ike ime n'oge usoro ahụ ma gbalịa ibelata ha, si otú a na-eme ka arụmọrụ nke injin okpomọkụ anyị emepụtara dịkwuo elu.
Ihe dị oke mkpa nke injin Carnot pụtara bụ na maka injin okpomọkụ zuru oke, okpomọkụ a na-enweta (QH ) kwekọrọ na okpomọkụ T H yana okpomọkụ a jụrụ (QL ) kwekọrọ na okpomọkụ T L. Ya mere, arụmọrụ nke injin okpomọkụ zuru oke bụ:
Ihe atụ ajụjụ nke atọ:
Injin uzuoku na-arụ ọrụ n'etiti 500 oC na 300 oC . Chọpụta arụmọrụ kachasị mma (arụmọrụ Carnot) nke injin uzuoku.
Mkparịta ụka
A ghaghị ịgbanwe okpomọkụ ahụ ka ọ bụrụ nha Kelvin.
T H (oke okpomọkụ) = 500 o C = 500 + 273 = 773 K
T L (okpomọkụ dị ala) = 300 o C = 300 + 273 = 573 K
Ọkwa kachasị mma ma ọ bụ arụmọrụ nke injin okpomọkụ zuru oke nke na-arụ ọrụ n'etiti 500 oC na 300 oC bụ 26%. Ọ bụrụ na injin anyị na-eji kwa ụbọchị na-arụ ọrụ n'etiti 500 oC na 300 oC , arụmọrụ kachasị elu nke injin ahụ nwere ike ime bụ ihe dị ka ugboro 0,7 nke arụmọrụ kachasị mma (18,2%).
Ihe atụ ajụjụ nke atọ:
Injin okpomọkụ na-enweta Joules 600 nke okpomọkụ (Q) na okpomọkụ nke 300 o C, na-arụ ọrụ Joules 100 (W) ma na-ajụ 500 J na okpomọkụ nke 100 o C. Chọpụta ezigbo arụmọrụ na arụmọrụ kacha mma (arụmọrụ Carnot) nke injin a...
Mkparịta ụka
A ghaghị ịgbanwe okpomọkụ ahụ ka ọ bụrụ nha Kelvin.
T H (oke okpomọkụ) = 300 o C ‐‐ 300 + 273 = 573 K
T L (okpomọkụ dị ala) = 100 o C ‐‐‐ 100 + 273 = 373 K
Q H = 600 J
Q L = 500 J
Arụmọrụ injin:
Arụmọrụ ma ọ bụ arụmọrụ kacha mma nke injin okpomọkụ zuru oke nke na-arụ ọrụ n'etiti 300 oC na 100 oC bụ 35%. Arụmọrụ kachasị elu nke injin ahụ nwere ike ime bụ ihe dị ka ugboro 0,7 arụmọrụ kachasị mma = 0,7 x 35% = 24,5% (24,5% x 600 J = 147 J nke okpomọkụ enwere ike iji rụọ ọrụ).
Ọrụ injin a n'ezie bụ 17% (naanị 100 J nke okpomọkụ ka eji arụ ọrụ). E ka nwere ihe dị ka 147 J – 100 J = 47 J nke okpomọkụ enwere ike iji rụọ ọrụ. Ọ ga-adị mma ma ọ bụrụ na a ga-eme ka arụmọrụ injin a dịkwuo elu iji belata mfu anyị na-enweta.
Ihe atụ ajụjụ nke atọ:
Igwe na-enweta 1000 Joules nke okpomọkụ ma na-emepụta 400 Joules nke ọrụ n'ime okirikiri ọ bụla. Igwe a na-arụ ọrụ n'etiti 500 oC na 200 oC . Kedu ezigbo arụmọrụ na arụmọrụ zuru oke nke igwe a?
Mkparịta ụka
T H (oke okpomọkụ) = 500 o C ‐‐‐ 500 + 273 = 773 K
T L (okpomọkụ dị ala) = 200 o C ‐‐‐ 200 + 273 = 473 K
Q H = 1000 J
Q L = 400 J
Arụmọrụ injin:
Ọrụ kachasị mma nke igwe a bụ:
Arụmọrụ kacha mma, nke a makwaara dịka arụmọrụ Carnot, bụ 40%. Arụmọrụ ezigbo injin bụ 60%. Injin dị otu a adịghị. Ọ gaghị ekwe omume ka arụmọrụ injin gafere arụmọrụ Carnot.
Ihe atụ ajụjụ nke atọ:
Iji mee ka arụmọrụ nke injin Carnot ruo 100% (1), kedu ihe achọrọ ka okpomọkụ ikuku (TL ) dị?
Mkparịta ụka
Iji mee ka arụmọrụ nke injin okpomọkụ zuru oke ruo 100% (enwere ike iji okpomọkụ ntinye niile rụọ ọrụ), okpomọkụ ikuku (TL ) ga-abụrịrị = 0 Kelvin.
Iru okpomọkụ nke 0 Kelvin agaghị ekwe omume. Okwu a bụ iwu nke atọ nke thermodynamics.
Ebe ọ bụ na ọ gaghị ekwe omume imezu 0 Kelvin, injin okpomọkụ zuru oke enweghị ike inwe arụmọrụ 100%. Ọbụna injin okpomọkụ zuru oke enweghị ike inwe arụmọrụ 100%, ma e wezụga injin okpomọkụ anyị na-eji kwa ụbọchị.
Ebe ọ bụ na injin okpomọkụ enweghị ike ịrụ ọrụ nke ọma 100%, anyị nwere ike ikwubi na ọ gaghị ekwe omume iji okpomọkụ ntinye niile (QH ) rụọ ọrụ. A ghaghị ịlafu okpomọkụ ụfọdụ (QL ).
Ọ gaghị ekwe omume ka injin okpomọkụ (na-arụ ọrụ n'ime okirikiri) gbanwee okpomọkụ niile ka ọ rụọ ọrụ (Iwu nke abụọ nke thermodynamics - nkwupụta Kelvin-Planck).
Ederede siri ike e ji aka dee n'elu bụ okwu pụrụ iche nke iwu nke abụọ nke thermodynamics. A na-akpọ ya nkwupụta pụrụ iche n'ihi na ọ na-emetụta naanị injin okpomọkụ. Ebe ọ bụ na Kelvin na Planck chepụtara ya, a na-akpọkwa ya nkwupụta Kelvin-Planck. Rịba ama ọnụnọ nke okwu ahụ bụ "okirikiri" na nkwupụta dị n'elu. Okirikiri bụ usoro nke na-eme ugboro ugboro. Ya mere, injin okpomọkụ na-arụ ọrụ mgbe niile. A na-agbakwụnye okwu ahụ bụ "okirikiri" n'ihi na, n'eziokwu, enwere ike ịgbanwe okpomọkụ niile ka ọ bụrụ ọrụ ma ọ bụrụ na usoro ahụ emee naanị otu ugboro.
N'iwu mbụ nke thermodynamics, a kọwara ọtụtụ usoro thermodynamic, gụnyere usoro isothermal, isobaric, isochoric, na adiabatic. N'usoro isothermal, enwere ike ịgbanwe okpomọkụ niile ka ọ bụrụ ọrụ (Q = W). Nke a nwere ike ime ma ọ bụrụ na usoro ahụ emee naanị otu ogbo. Lee onyonyo dị n'okpuru:
Eserese a na-egosi usoro isothermal (mgbasawanye isothermal) nke na-eme n'otu nzọụkwụ. N'ime usoro a, a na-agbanwe okpomọkụ niile (Q) ka ọ bụrụ ọrụ (W). Ọnụọgụ ọrụ emere = mpaghara agba.
Iji baa uru, injin okpomọkụ ga-arụ ọrụ mgbe niile (usoro a ga-eme ugboro ugboro, ọ bụghị naanị n'otu ogbo). Dịka ọmụmaatụ, injin steam na-agbanwe agbanwe. Piston dị na injin steam na-agbanwe agbanwe ga-aga n'aka nri na aka ekpe mgbe niile ka wiil ahụ wee nwee ike ịtụgharị (enwere ike iji ya bugharịa ihe). Wheel enweghị ike ịtụgharị ma ọ bụrụ na piston ahụ na-aga naanị n'aka nri, mgbe nke ahụ gasịrị ọ na-akwụsị (usoro ahụ na-eme naanị n'otu ogbo). Ọ bụrụ na usoro ahụ emee ugboro ugboro (piston ahụ na-aga n'aka nri na aka ekpe mgbe niile), ọ gaghị ekwe omume ka a gbanwee okpomọkụ niile ka ọ bụrụ ọrụ (nkwupụta Kelvin-Planck). Dịka ọmụmaatụ, ka anyị tụlee usoro isothermal egosiri na eserese dị n'elu.
Grafụ dị n'aka ekpe na-egosi mgbasawanye isothermal (akụ ala) na mkpụkọ isothermal (akụ elu). Usoro a na-eme mgbe niile n'ụzọ isothermal (anaghị arụ ọrụ ọ bụla). Grafụ dị n'aka nri na-egosi mgbasawanye isothermal (akụ ala), mkpụkọ isobaric (akụ aka ekpe), na usoro isochoric (akụ elu). Site na eserese abụọ a, o doro anya na maka usoro ndị na-eme mgbe niile (okirikiri), enwere mkpụkọ okpomọkụ mgbe niile. Nke a kwekọrọ na nkwupụta Kelvin-Planck gara aga.
