Maitiro eThermodynamic echinyorwa: Isothermal Adiabatic Isochoric Isobaric
Kune maitiro mana ethermodynamic, anoti Isothermal, isochoric, isobaric uye adiabatic.
Maitiro eIsothermal (tembiricha inogara iripo)
Munzira ye isothermal, tembiricha yesystem inochengetwa yakafanana. Mupfungwa, sisitimu yakaongororwa igesi yakakodzera. Tembiricha yegesi yakakodzera inoenderana zvakananga nesimba remukati regesi (U = 3/2 n RT). T haichinji, saka U haichinjiwo. Saka, kana ikashandiswa kune isothermal process, mutemo wekutanga we thermodynamic equation unova:
Δ U = Q – W
Simba remukati harichinji, saka Δ U = 0.
0 = Q – W
Q = W
Zvichibva pachiyero ichi, mukuita kwe isothermal (nguva dzose tembiricha), kupisa (Q) kunowedzerwa kusystem kunoshandiswa nesystem kuita basa (W).
Kuchinja kwekumanikidzwa uye huwandu hwehurongwa mumaitiro e-isothermal kunoratidzwa negirafu iri pazasi:
Vhoriyamu yekutanga yesystem = V1 (vhoriyamu diki) uye kumanikidzwa kwesystem = P1 (kumanikidzwa kukuru). Kuti tembiricha yesystem igare yakafanana, mushure mekunge kupisa kwawedzerwa kusystem, system inokura uye inoshanda pane nharaunda. Mushure mekunge system yashanda pane nharaunda, vhoriyamu yesystem inoshanduka kuita V2 (huwandu hwesystem hunowedzera) uye kumanikidzwa kwesystem kunochinja kuenda kuP2 (kudzikira kwekumanikidzwa kwesystem). Chimiro chegirafu chakakombama nekuti kumanikidzwa kwesystem hakuchinji nguva nenguva panguva yekuita. Huwandu hwebasa raitwa system = nzvimbo ine mumvuri.
Maitiro eAdiabatic
Mukuita kweadiabatic, hapana kupisa kunowedzerwa kusystem kana kubuda musystem (Q = 0). Maitiro eAdiabatic anogona kuitika musystem dzakavharwa dzakanyatsoganhurirwa. Kune system yakavharwa yakavharirwa zvakanaka, kazhinji hapana kupisa kunoyerera musystem kana kubuda musystem. Maitiro eAdiabatic anogonawo kuitika musystem dzakavharwa dzisina kuganhurirwa.
Muchiitiko ichi, maitiro acho anofanira kuitwa nekukurumidza kuitira kuti kupisa kusayerere musystem kana kubuda musystem. Kana ikashandiswa kune adiabatic process, mutemo wekutanga Thermodynamic equation ichachinja:
Δ U = Q – W
Hapana kupisa kuri mukati kana kunze kwesystem, saka Q = 0.
Δ U = 0 – W
Δ U = -W
Kana sisitimu ikamanikidzwa nekukurumidza (basa raitwa pasisitimu), saka basa racho rinova negative. Nekuti W iri negative, saka U iri positive (simba riri musisitimu rinowedzera). Kusiyana neizvi, kana sisitimu ikakura nekukurumidza (sisitimu inoshanda), saka W iri positive. Sezvo W iri positive, U iri negative (simba riri musisitimu rinodzikira). Simba riri musisitimu (gasi rakakodzera) rinoenderana netembiricha (U = 3/2 n RT), saka kana simba riri musisitimu rikawedzera saka tembiricha yesisitimu inowedzerawo. Kusiyana neizvi, kana simba riri musisitimu rikadzikira, saka tembiricha yesisitimu inodzikira.
Kuchinja kwekumanikidzwa kwesystem uye vhoriyamu mukuita kweadiabatic kunoratidzwa negirafu iri pazasi:
Mutsetse weadiabatic uri pagirafu iyi (macurve 1-2) wakadzika kupfuura mutsetse weisothermal (macurve 1-3). Musiyano uyu wekudzika unoratidza kuti pakuwedzera kwevhoriyamu imwe chete, kumanikidzwa kwesystem kunodzikira zvakanyanya mukuita kweadiabatic kupfuura muitiro weisothermal. Kumanikidzwa kwesystem kunodzikira zvakanyanya mukuita kweadiabatic nekuti kana adiabatic yakawedzera, tembiricha yesystem inodzikirawo. Tembiricha inoenderana nekumanikidzwa, saka kana tembiricha yesystem ikadzikira, kumanikidzwa kwesystem kunodzikirawo. Kusiyana nemaitiro eisothermal, tembiricha yesystem inogara iripo. Saka, mukuita kweisothermal, tembiricha haikanganisi kudonha kwepressure.
Muenzaniso mumwe wemaitiro e adiabatically unoitika muinjini yekupisa mukati, senge injini yedhiziri neinjini yepeturu. Muinjini dzedhiziri, mweya unopinzwa mu cylinder, uye mweya uri mukati me cylinder unopinzwa nekukurumidza uchishandisa piston (basa rinoitwa mumhepo). Maitiro ekumanikidza adiabatic (kuderedza huwandu hwesimba rehurongwa) anoratidzwa ne curve 2-1. Nekuda kwekumanikidzwa nekukurumidza kwe adiabatic, tembiricha inokwira nekukurumidza. Panguva imwe chete, dhiziri rinopfapfaidzwa mu cylinder kuburikidza ne injector, uye musanganiswa wacho unokasira kutangwa. Muinjini yepeturu, musanganiswa wemhepo nepeturu unopinzwa mu cylinder wobva wadzvanywa nekukurumidza uchishandisa piston. Nekuti inosundidzirwa nekukurumidza, tembiricha inokwira nekukurumidza. Panguva imwe chete, spark plugs dzinobvira moto kuitira kuti maitiro ekupisa aitike.
Maitiro eIsochoric (huwandu hunogara huripo)
Munzira yeIsochoric, vhoriyamu yesystem inochengetwa yakafanana. Sezvo vhoriyamu yesystem ichigara yakafanana, system haigone kushanda pane nharaunda. Nzvimbo haigonewo kushanda pane system. Kana ikashandiswa kune nzira yeisochoric, mutemo wekutanga we thermodynamic equation unoshanduka kuita:
Δ U = Q – W
Sisitimu iyi haishande pane zvakatipoteredza, saka W = 0
Δ U = Q – 0
Δ U = Q
Kubva pane izvi, tinogona kugumisa kuti mukuita kwe isochoric (constant volume), kupisa (Q) kunowedzerwa musystem kunoshandiswa kuwedzera simba musystem. Kuchinja mukumanikidzwa kwesystem uye volume mukuita kwe isochoric zvinoratidzwa negirafu iri pazasi:
Pakutanga, kumanikidzwa kwesystem = p 1 (kumanikidzwa kudiki). Kupisa kwakawedzerwa kwesystem kunoita kuti simba riri musystem riwedzere. Sezvo simba riri musystem richiwedzera, tembiricha yesystem (gasi rakakodzera) inowedzera (U = 3/2 n RT). Tembiricha inoenderana zvakananga nekumanikidzwa. Saka, kana tembiricha yesystem ikawedzera, kumanikidzwa kwesystem kunowedzera (p 2 ). Nekuda kwehuwandu hwesystem hunogara huripo, hapana basa rinoitwa (hapana nzvimbo ine mumvuri).
Mukuita kwe isochoric, sisitimu haigone kushanda panzvimbo. Saizvozvowo, nzvimbo haigone kushanda panzvimbo. Izvi zvinodaro nekuti, mukuita kwe isochoric, vhoriyamu yesisitimu inogara yakadaro. Kune mamwe marudzi ebasa asingasanganisi kuchinja vhoriyamu. Saka kunyangwe vhoriyamu yesisitimu isingachinje, basa rinogona kuitwa panzvimbo yacho. Semuenzaniso, pane feni + bhatiri mumudziyo wakavharwa. Fani inogona kutenderera ichishandisa simba nebhatiri. Muchiitiko ichi, mafeni, mabhatiri, nemhepo iri mukati memudziyo zvinoonekwa semasisitimu.
Kana feni ikatenderera, feni inoshanda, ichitamba iri mumudziyo. Panguva imwe chete, simba remagetsi refeni rinoshanduka kuita simba mumhepo. Simba remagetsi mubhatiri, hongu, rinodzikira nekuti rakachinja chimiro kuita simba mumhepo. Muenzaniso uyu unoratidza kuti mukuita kwe isochoric (vhoriyamu inogara iripo), basa rinogona kuitwa pasystem (basa risingasanganisi kuchinja kwevhoriyamu).
Maitiro eIsobaric (kumanikidzwa nguva dzose)
Mumaitiro e-isobaric, kumanikidzwa kwesystem kunochengetwa kwakafanana. Sezvo kumanikidzwa kuri kwakafanana, shanduko yesimba remukati ( Δ U), kupisa (Q) uye basa (W) mumaitiro e-isobaric hazvisi zero. Saka, fomura yekutanga yethermodynamics haina kuchinja.
ΔU = Q − W
Kuchinja mukumanikidzwa uye huwandu hwegasi mumaitiro e-isobaric zvinoratidzwa negirafu iri pazasi:
Chekutanga, vhoriyamu yesystem = V1 (vhoriyamu diki). Nekuti kumanikidzwa kunochengetwa kwakafanana, saka mushure mekunge kupisa kwawedzerwa kusystem, system inokura uye inoshanda pane nharaunda. Mushure mekushanda pane nharaunda, vhoriyamu yesystem inoshanduka kuita V2 (kuwedzera kwehuwandu hwesystem). Huwandu hwebasa (W) system yaitwa = nzvimbo ine mumvuri.
Mubvunzo wechi1:
Makombama 1-2 mumadhayagiramu maviri ari pazasi anoratidza kuwedzera kwegasi (kuwedzera kwehuwandu hwegasi) kunoitika adiabatically uye isothermally. Mukuita kupi, basa rinoitwa negasi diki?
Basa rinoitwa nemagasi mu adiabatic process harisi basa rinoitwa nemagasi mu isothermal process. Nzvimbo ine mumvuri = basa rinoitwa negasi panguva yekuwedzera (kuwedzera kwehuwandu hwegasi). Nzvimbo ine mumvuri mu adiabatic process iri pasi penzvimbo ine mumvuri ye isothermal process.
Mubvunzo wechi2:
Maitiro eThermodynamic anoratidzwa mudhayagiramu iri pazasi. Makombo ab na dc = maitiro e isochoric (huwandu hunogara huripo). Makombo bc na ad = maitiro e isobaric (kumanikidzwa kunogara kuripo). Mumaitiro e ab, kupisa (Q) 600 Joules kunowedzerwa kuhurongwa. Mumaitiro e bc, kupisa (Q) 800 Joules kunowedzerwa kuhurongwa.
a) Kuchinja kwesimba mukuita kwe ab
b) Shanduko dzesimba mumaitiro eabc
c) Kupisa kwese kwakawedzerwa kune maitiro eADC
P 1 = 2 x 10 5 Pa = 2 x 10 5 N / m 2
P 2 = 4 x 10 5 Pa = 4 x 10 5 N / m 2
V 1 = 2 marita = 2 dm 3 = 2 x 10 -3 m 3
V 2 = marita mana = 2 dm 3 = 4 x 10 -3 m 3
mhinduro
a) Kuchinja kwesimba remukati mukuita kweab
Mukuita kwe ab, kupisa kwe 600 J kunowedzerwa mu system. Maitiro e ab = isochoric process (constant volume). Mukuita kwe isochoric, kuwedzerwa kwekupisa mu system kunongowedzera simba mu system. Saka, simba rinoshanduka mu system mushure mekugamuchira kupisa:
ΔU = Q
ΔU = 600 J
b) Shanduko dzesimba mumaitiro eabc
Maitiro ab = maitiro e-isochoric (vhoriyamu isingaperi). Mumaitiro e-ab, kupisa kwe600 J kunowedzerwa kuhurongwa. Nekuda kwehuwandu hunogara huripo, hapana basa rinoitwa nehurongwa.
Maitiro e bc = maitiro e isobaric (kumanikidzwa nguva dzose). Mumaitiro e bc, kupisa (Q) 800 Joules kunowedzerwa kuhurongwa. Mumaitiro e isobaric, hurongwa hunogona kushanda. Huwandu hwebasa rinoitwa nehurongwa mumaitiro e bc (maitiro e isobaric) nde:
W = P (V 2 – V 1 ) — kumanikidzwa kunogara kuripo
W = P 2 (V 2 – V 1 )
W = 4 x 10 5 N/m 2 (4 x 10 -3 m 3 – 2 x 10 -3 m 3 )
W = 4 x 10 5 N/m 2 (2 x 10 -3 m 3 )
W = 8 x 10 2 Joule
W = 800 Joule
Kupisa kwese kunowedzerwa kuhurongwa mu abc process ndekwekuti:
Q huwandu = Q ab + Q bc
Huwandu hwese hweQ = 600 J + 800 J
Huwandu hweQ = 1400 Joules
Basa rose rinoitwa nehurongwa mu abc process nderinotevera:
huwandu hweW = W ab + W bc
huwandu hweW = 0 + W bc
Huwandu hwese = 0 + 800 Joule
H yose = 800 Joule
Kuchinja kwesimba remukati mukuita abc = 600 J
c) Kupisa kwese kwakawedzerwa kumaitiro eADC
Kupisa kwese kunowedzerwa kuhurongwa kunogona kuverengerwa ne equation iri pazasi:
ΔU = Q - W
Q = ΔU + W
Kupisa kwese kwakawedzerwa kuprocess adc = shanduko dzesimba remukati muADC + basa muprocess adc.
Kupisa nebasa zvinosanganisirwa mukufambiswa kwesimba pakati pemasisitimu nenzvimbo, nepo shanduko dzesimba remukati dziri mhedzisiro yekufambiswa kwesimba pakati pesisitimu nenzvimbo. Naizvozvo, shanduko yesimba haitsamiri pakufambisa simba. Kune rumwe rutivi, kupisa nebasa zvinoenderana nemaitiro acho. Mukuita kweisochoric (system yehuwandu hunogara huripo), kutamiswa kwesimba kunongoitika muchimiro chekupisa, nepo basa risingashande. Mukuita kweisobaric (kumanikidzwa nguva dzose), kutamiswa kwesimba kunosanganisira kupisa nebasa. Kunyangwe zvisingatsamiri pakuita, simba rinoshanduka zvichienderana nemamiriro ekutanga uye mamiriro esystem yekupedzisira. Kana mamiriro ekutanga neekupedzisira akafanana, shanduko musimba dzinogara dzakafanana, kunyangwe maitiro acho akasiyana.
Mamiriro ekutanga neokupedzisira emaitiro eabc mugirafu riri pamusoro = mamiriro ekutanga neokupedzisira emaitiro eadc. Saka, simba remukati rinoshanduka mumaitiro eadc = 600 J.
Basa rose (W) rakaitwa pa adc = W process pa ad + W pa dc process.
Maitiro ekushambadzira inzira ye isobaric (constant pressure), nepo maitiro e dc ari maitiro e isochoric (constant volume). Nekuda kwehuwandu hunogara huripo, hapana basa rinoitwa pamaitiro e dc. Kutanga, tinoverenga basa rinoitwa pamaitiro ekushambadzira.
W ad = P (V 2 - V 1 )
W ad = P 1 (V 2 - V 1 )
Wadhi = 2 x 10 5 N/m 2 (4 x 10 ‐3 m 3 ‐ 2 x 10 ‐3 m 3 )
Wadhi = 2 x 10 5 N/m 2 (2 x 10 ‐3 m 3 )
W ad = 4 x 10 2 Joule
W ad = 400 Joule
W huwandu = W mukuita a-d + W mukuita d-c
Huwandu hwese = 400 Joules + 0
H yose = 400 Joule
Saka, huwandu hwekupisa hunowedzerwa kune maitiro eADC ndehwekuti:
Q = ΔU + W
Q = 600 J + 400 J
Q = 1000 J
Mubvunzo wechi3:
1 litre yemvura inoshanduka kuita 1671 litres yeutsi kana yabikwa pa1 atm pressure. Verenga shanduko yesimba remukati uye basa rinoitwa nemvura kana yapwa … (Kupisa kweutsi hwemvura = L V = 22.6 x 10 5 J/Kg)
mhinduro
Kuwanda kwemvura = 1000 kg/ m3
Kupisa kwekupfuta kwemvura (L V ) = 22.6 x 10 5 J / Kg
P = 1 atm = 1.013 x 10 5 Pa = 1.013 x 10 5 N/m 2
V 1 = 1 litre = 1 dm 3 = 1 x 10 -3 m 3 (Huremu hwemvura)
V 2 = 1671 marita = 1671 dm 3 = 1671 x 10 -3 m 3 (Huwandu hwemhepo inopfungaira)
a) Kuchinja kwesimba remukati
Kuchinja kwesimba remukati = Kupisa kwakawedzerwa mumvura kubvisa Basa rinoitwa nemvura kana yapwa. Kuverenga kwekutanga Kupisa (Q) kwakawedzerwa mumvura …
Q = m L V
Kuwanda kwemvura = huremu hwemvura / huwandu hwemvura
Huremu hwemvura (m) = kuwanda kwemvura x huwandu hwemvura
Huremu hwemvura (m) = (1000 kg/m3 ) ( 1 x 10 -3 m3 )
Huremu hwemvura (m) = (1000 kg/m3 ) (0.001 m3 )
Huremu hwemvura (m) = 1 kg
Q = (1 kg) (22.6 x 10 5 J / kg)
Q = 22.6 x 10 5 J
Verenga basa (W) rinoitwa nemvura kana yapwa. Kufashaira kwemvura kunoitika nekumanikidzwa kwakasimba (isobaric process).
W = p (V 2 – V 1 )
W = 1.013 x 10 5 N/m 2 (1671 x 10 -3 m 3 – 1 x 10 -3 m 3 )
W = 1.013 x 10 5 N/m 2 (1670 x 10 -3 m 3 )
W = 1691.71 x 10 2 Joule
W = 1.7 x 105 Joules
Kuchinja kwesimba remukati memvura:
ΔU = Q - W
ΔU = 22.6 x 10 5 J – 1.7 x 10 5 J
ΔU = 20.9 x 10 5 J
ΔU = 21 x 10 5 J
21 x 10 5 Joule kupisa kunowedzerwa mumvura kunoshandiswa kuwedzera simba remukati (kukunda masimba ekumanikidzana pakati pemamorekuru anochengetedza mvura ichiyerera). Nemamwe mashoko, 21 x 10 5 J inoshandiswa kushandura mvura kuita utsi. Kana mvura yava utsi, 1.7 x 105 J yasara inoshandiswa kuita basa.
Mubvunzo wechi4:
Mole imwe chete yegasi mu cylinder inokura nekukurumidza sezvinoita adiabatically. Pakutanga, tembiricha yegasi = 1000 K. Mushure mekukura, tembiricha yegasi inoderera kusvika 500 K. Sarudza basa rinoitwa negasi …
mhinduro
Kukura kwegasi kunoitika panguva yeadiabatic. Mukuita kweadiabatic, hapana kupisa kunopinda kana kubuda musystem. Saka, basa rinoitwa mugasi = shanduko dzesimba mugasi.
ΔU = Q – W kana W = Q – Δ U → Q = 0
W = 0 – ΔU
W = – ΔU
Tinogona kuverenga shanduko dzesimba mugasi tichishandisa equation yesimba mugasi rakakodzera:
ΔU = 3/2 (1 mol) (8.315 J / mol. K) (500 K – 1000 K)
ΔU = 3/2 (1 mol) (8.315 J / mol. K) (- 500 K)
ΔU = -6236.25 J
Saka, huwandu hwebasa rinoitwa negasi ndehwekuti:
W = – ΔU
W = – (- 6236.25 J)
W = 6236.25 J
