Pūkaha Heat: he huringa, te mahi tōtika. raruraru Taiao o mihini waiariki. He aha te mea te reira - he pūkaha wera pai?

Ko te hiahia mo te whakamahi o te pūngao pūkaha i arahina i roto i te hanga ki te putanga o mihini waiariki.

Ko te kōwae o engines wera

engine Heat (pūkaha wera), - he pūrere mō te tahuri pūngao ā-ki pūngao pūkaha.

Tetahi pūkaha wera he whakamahana, te inu mahi (hau kohu ranei), i mahi mahi i te whakawera (hua i roto i te hurihanga o te take mīhini huri hiko, nga nekehanga kōkeke, a pera i runga i) me te pouaka. Ko te ahua i raro whakaatu he hoahoa o te pūkaha wera.

Taketake takahanga o engines wera

Ia mahi pūkaha wera e tika ana ki te pūkaha. Ki te mahi i te mahi e hiahiatia ana e ia ki runga i tetahi taha o te kōkeke pūkaha mīhini huri hiko ranei matatahi ko pēhanga rerekētanga. tutuki ana tēnei rerekētanga i roto i nga engines katoa wera e whai ake: kua nui haere te pāmahana inu mahi ki rau mano ranei o nga nekehanga whakaritea ki te pāmahana ambient. I roto i te kapohau hau me engines ngingiha ā (tio) ko he hua i roto i te pāmahana e tika ana ki te meka i tahuna te wahie i roto i te pūkaha. Ka taea e pouaka mahi huru pūrere whakaaro motuhake ranei mo te meangiti me te tōtā te te mamaoa pau.

huringa Carnot

Porohita (tukanga huringa) - he huinga o ngā huringa hau huru, hua i roto i te reira e hoki mai ki te āhua tuatahi (ka taea te mahi i mahi). I roto i te 1824, whakaaturia te ahupūngao French Sadi Karno, he pai ki te huringa pūkaha wera (te huringa Carnot), e ngā o ngā tukanga e rua - te isothermal me adiabatic. Ko te ahua i raro whakaatu he kauwhata o te huringa Carnot: 1-2 me 3-4 - isotherm, 2-3 me 4-1 - adiabatic.

I roto i runga i te ture o te tiaki o te mahi pūngao o engines wera i mahi pūkaha ko:

A = Q ₁ - Q _2,

₁ te wahi Q - nui o te wera riro nei i te whakamahana, a ₂ Q - nui o te wera kopani e e te ki te pouaka.
Kakama ko te ōwehenga o te pūkaha wera mahi A e puta ia te pūkaha ki te nui o te wera whiwhi nei i te whakamahana:

η = A / Q = (Q ₁ - Q ₂₎ / Q ₁ = 1 - Q ₂ / Q _1.

I roto i "Thoughts i runga i te mana turai o te ahi, me te i runga i ngā mīhini e e taea ki te whakawhanake i tenei ope" (1824) whakaahuatia te pūkaha wera Carnot i raro i te ingoa "pūkaha wera pai ki te hau pai, i te mea he tino mahi." Nā ki te ture o thermodynamics taea tātai i te tōtika (te mōrahi ka taea) ki te whakamahana pūkaha wera i he T pāmahana _1, me te pouaka he T pāmahana _2. Carnot tōtika pūkaha wera ko:

η _max = (T ₁ - T ₂₎ / T ₁ = 1 - T ₂ / T _1.

whakamatauria Sadi Karno e kore te mīhini hiahiatia waiariki tūturu, e mahi ki te whakamahana me te pāmahana T ₁ me te condenser i te T pāmahana ₂ e taea ki te whai tōtika i pai nui i te tōtika o te pūkaha wera (pai).

pūkaha ngingiha ā-(tio)

E wha-patunga engine ngingiha ā ngā kotahi, neke atu rānei ipurau, he kōkeke, he tikanga ratchet, rōpū, me te whakapau vaolo, korakora.

Kei te huringa whakahaere o wha whiu:

1) te ngote - haere ranunga combustible roto i te piha ki te rango;
2) Kōpeketanga - katia vaolo e rua;
3) patunga - te ngingiha taikaha o te ranunga combustible;
4) whakapau - te tuku hau whakapau ki te kōhauhau.

mīhini huri hiko mamaoa

puta te faafariuraa pūngao mamaoa mīhini huri hiko e tika ana ki te rerekētanga o te mau faaheporaa kohu wai i te kokoru me putanga.
Power o kapohau korohū hou tae 1,300 MW.

Ētahi tawhā hangarau o te mamaoa mīhini huri hiko 1,200 MW

• pēhanga kohu (hou) - 23.5 MPa.
• pāmahana Steam - 540 ° C.
• Steam mīhini huri hiko rere - 3600 m / h.
• tere rotor - 3000 REV / min.
• Te pēhanga kohu i roto i te condenser - 3.6 kPa.
• mīhini huri hiko Length - 47.9 m.
• mīhini huri hiko Mass - 1900 m.

Kei mīhini waiariki o te mīhini huri hiko rangi compressor, combustor me te hau. OPERATION: adiabatically te ngote hau ki roto ki te compressor, na te whakaarahia ona pāmahana ki te 200 ° C neke atu rānei. Next, te rangi kōpeke tomo te ruma ngingiha wahi pēhanga teitei wā kotahi tukua wahie wai - karahīni hinu photogen wahie. I roto i te parariraa o te wahie rangi kua oti te tahu ki te pāmahana o 1500-2000 ° C, fakalahi reira me whakanuia ana tona tere. neke te rangi i te tere tiketike, a ka kua whakahaua nga hua parariraa ki te mīhini huri hiko. I muri i te whakawhitinga i te atamira ki matatahi mīhini huri hiko atamira ngingiha hoatu tona pūngao neke. Wāhanga o te pūngao riro e te mīhini huri hiko, ko te hurihanga compressor; pau te wahi e toe ana i runga i te rotor generator, rotor rererangi ranei te oko moana, he wira waka.

Ka taea te whakamahi i te mīhini huri hiko hau, haunga te waka rererangi takahuri me nga wira waka propellers ranei o te kaipuke, ka rite ki te pūkaha jet. E pana Air me ngingiha hau i tere tiketike i te mīhini huri hiko hau, na te akina jet i whakatika i roto i tenei tukanga kia whakamahia ai ki te neke rererangi (manureva) me te wai (kaipuke) kaipuke, tereina waka. Hei tauira, engines turboprop whai rererangi AN-24, AN-124 ( "Ruslan"), Ru-225 ( "Dream"). Ko te kupu, ko te "Dream" i te tere e rere o 700-850 km / h Ko te ahei o mau ana 250 taranata o te utanga ki runga i te tawhiti o tata 15,000 kiromita. Ko te reira i te rererangi waka nui rawa i roto i te ao.

raruraru Taiao o mihini waiariki

pānga nui i runga i te āhuarangi ko tikanga kōhauhau, ngā te aroaro o te te hauhā me te kohu wai. Ko te kupu, ko te huringa i roto i te te ihirangi hauhā arata'i ki te hua ranei hekenga i roto i te kati kōtuhi, i roto i nei hauhā absorbs etahi o te wera e turamaraa i ki wāhi te whenua, takaroa i roto i nga piki huru, me te kupu i te pāmahana mata me te huru o raro. Ko te āhuatanga o te kati kōtuhi whai wāhi tino hira i roto i te āhuarangi mitigation. I roto i tona ngaro, te pāmahana toharite o te ao e kore e +15 ° C me te raro e 30-40 ° C.

i roto i te ao i reira e teie nei neke atu i te 300 miriona ngā momo o waka, e hanga neke atu i te hawhe o te parahanga rangi katoa.

tohaina Neke 1 tau ki te huru i te kaha waiariki i te parariraa o te wahie e 150 miriona toni o waikura whanariki, 50 miriona toni o hauota waikura, 50 miriona toni o pungarehu, 200 miriona toni o te waro haukura, 3 miriona toni Feona.

Ko te hanganga o te kōhauhau ngā pekerangi, e tiaki ora katoa i runga i te whenua i te pānga ino o hihi katinga. . I te 1982, John Farman, te kaihōpara o Ingarangi, i kitea ki runga Antarctica ozone rua - he whakaiti rangitahi o te ihirangi Ozone i roto i te huru. I te tihi o te pekerangi poka 7 nuku 1987 kua heke te nui o te pekerangi i roto i te reira i roto i te 2 nga wa. pea hua ozone poka i ngā āhuatanga horonga, tae atu whakamahi i roto i te ahumahi o freons māota-kei roto (CFC), e whakangaro te pekerangi. Heoi, ko te ako 1990. e kore whakapumautia tenei tirohanga. Te nuinga pea, e kore te mea e pā ana ki ngā mahi tangata te putanga o te poka pekerangi, a ka he te tukanga māori. I roto i te 1992, kitea te poka te pekerangi i runga i te Arctic.

Ki te kohikohi i te apa pekerangi kōhauhau katoa i roto i te mata o te whenua, a takaete reira ki te kiato o te rangi i te pēhanga kōhauhau me te pāmahana o te 0 ° C, ka ozone whakangungu rakau matotoru, ko te 2-3 anake mm! Ko te te whakangungu rakau katoa.

He bit o hītori ...

• Hōngongoi 1769. I roto i Paris Meudon park hōia kaipūkaha NZ Kyunyo ki "pereoo ahi", i rite rawa ki te pūkaha korohū e rua-rango, peia he torutoru tekau o mita.
• 1885. Karl Benz, he mataaro Tiamana, hanga te mana tuatahi e wha-moana penehīni car Motorwagen o 0.66 Kw, 29 Kohitātea 1886 i whiwhi te ārai. tere Machine ko 15-18 km / h.
• 1891. Gottlieb Daimler, he ihi Tiamana, trolley hangaia peia mana 2.9 Kw (4 horsepowers) o te motokā. Ko te tere mōrahi o te waka tae 10 km / h, te kaha i roto i te tauira rerekē ko i te 2 ki te 5 taranata.
• 1899. Belgian K. Zhenattsi i tona waka, "Jamet Contant" ( "kore makona") mo te wa tuatahi whiti te tere rārangi 100-kiromita.

Tauira o whakaoti rapanga

Raruraru 1. Ko te pāmahana o te pūkaha wera pai whakamahana he rite ki te 2000 K, me pouaka pāmahana - 100 ° C. Hei whakatau i te tōtika.

otinga:
Ko te tātai e whakatau te tōtika o te pūkaha wera (mōrahi):

n = T ₁ T ₂ / T _1.
N = (2000K - 373K) / 2000 K = 0,81.

tōtika pūkaha - 81%: A.

Raruraru 2. Ko te pūkaha wera 200 kJ o te wera i whiwhi e te parariraa o wahie, ka whakawhiti ki te mātao 120 kJ te wera. He aha te mea te tōtika o te pūkaha?

otinga:
Ko te tātai mō te whakatau i te tōtika ko o te puka:

N = Q1 - Q2 / Q1.
n = (2 × 10 ⁵ J - 1.2 x 10 ⁵ J) / 2 x 10 ⁵ J = 0.4.

A: Ko te tōtika waiariki o te pūkaha - 40%.

Problem 3. He aha te mea te tōtika o te pūkaha wera, ka whakamana i te wai mahi i te whakamahana i muri i te fariiraa i te nui o te wera o 1.6 MJ mahi 400 kJ? He aha te mea te nui o te wera i whakawhitia ki te pouaka?

otinga:
taea te kaha te whakaritea e te tātai

N = A / Q _1.

n = 0.4 · 10 ⁶ J / 1.6 · 10 ⁶ J = 0.25.

Ka taea e rahinga wera pouaka tuku kia whakaritea e te tātai

Q ₁ - A = Q _2.
Q ₂ = 1.6 · 10 ⁶ J - 0.4 · 10 ⁶ J = 1.2 · 10 ⁶ J.
A: Ko te pūkaha wera he pai o 25%; rahinga o te wera whakawhiti ki te pouaka - 1.2 · 10 ⁶ J.