Heat engine: ka pōʻaiapuni, o ka hana ka hoʻokōʻana. ? Aneie pilikia o thermal machines. He aha ka mea - he maikaʻi ka wela engine?

Ka pono no ka pono o me mechanical ikehu i? Iecaianoaaiiuo ua alakai ai i ka muli o thermal machines.

Ke pa alima o ka wela kiko'ī

Heat engine (wela engine), - he mea no ka hoʻololi 'ana i na ikehu i loko o me mechanical ikehu.

Kekahi wela engine mai kekahi iaia? Aaaoaeuiuo, ka hana loli (kinoea make a me ka ohu), i hanaʻia hana ma ka paio hahana maoli nō (kūpono ma kuapo o ka mīkini peahi uila kumu, ke kuʻe e neʻe aku, a no laila, ma) a me ka Pahu Hau. Me ke kiʻi ma lalo hōʻike he kiʻikuhi o ka wela engine.

Kumu o ke kapuwai o ka wela kiko'ī

Kēlā me kēia wela engine functioning ku i ka engine. E hana i ka hana ia i nele i ia ma kekahiʻaoʻao o ka engine kuʻe a mīkini peahi uila kōmi 'ua puʻe like. Ua like ua loaʻa i loko o nā mea a pau i ka wela kiko'ī like penei: ua hoomahuahua ia ka hana loli mahana i ka haneri, a me na tausani o nā degere hoohalikeia me ka Ambient mahana. I kinoea turbines a me na'ā kiko'ī (hau) mea he mahuahua i ana wela no i ka mea i ka wahie ua kuni i ka mea i loko o ka engine. Pahu Hau ke hana lewa a me keia manaʻo no ka anuanu a Punk i ka pau keia la mahu.

Carnot pōʻaiapuni

Kalapona (cyclic kaʻina) - he lākou o ke kinoea kulana loli, kūpono ai i loko o ka mea, ua hoʻi mai i ka loiloi mua moku'āina (hiki ke hana hana). I ka 1824, he Palani physicist Sadi Karno hōʻike i ia mea mea eʻoi aʻe ka wela engine kalapona (ka Carnot kalapona), a he mau keʻano o ka hanaʻana - i ke isothermal a me ka adiabatic. Me ke kiʻi ma lalo hōʻike i ka pakuhi o ka Carnot kalapona: 1-2 a 3-4 - isotherm, 2-3 a 4-1 - adiabatic.

I kulike ai me ke kānāwai o ka mālama o ka ikaika hana o ka wela kiko'ī i hanaʻia engine mea:

A = Q ₁ - Q _2,

₁ kahi Q - nui o ka wela i ua loaa mai ka iaia? Aaaoaeuiuo, a me ₂ Q - nui o ka wela i ua waihoia ma ka Pahu Hau.
Ka hoʻokōʻana o ka lākiō o ka wela engine hana A i hoʻokō iho au i ka engine a hiki i ka nui o ka wela i ua loaa mai ka iaia? Aaaoaeuiuo:

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

Ma "manaʻo ma luna o ka maka pua mana o ke ahi, a ma luna o machines mea e hiki ke kūkulu i keia poe a pau" (1824) i ho'ākāka 'ia i ka Carnot wela engine ma lalo o ka inoa "maikaʻi wela engine me ka maikaʻi kinoea, a mea e hana ana i ke kino." Manawa i na kanawai o thermodynamics ke ho omaulia i ka ka hoʻokōʻana (ka mea i kā mākou hiki) me ka wela engine iaia? Aaaoaeuiuo a mea he wela T _1, a me ka Pahu Hau me ka wela T _2. Carnot wela engine ka hoʻokōʻana o:

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

Sadi Karno hoao i ka makemake thermal maoli mīkini, i hana ia me ka iaia? Aaaoaeuiuo me ka mahana T ₁ a me ka condenser ma ka wela T ₂ mea,ʻaʻole hiki ke i ka hoʻokōʻana i makemake oi i ka ka hoʻokōʻana o ka wela engine (maikaʻi).

Kūloko'ā engine (hau)

Four-mapuna maloko'ā engine maupaʻa kekahi a oi nā paukūʻolokaʻa, he kuʻe, he crankʻano papa hana,ʻai ana, a no ka maluhiluhi kiwikā, hunaahi.

Ka pae'ōnaehana kalapona ninoieo o ka eha hahau ana:

1) i ke keiki omo - combustible ukuhiia hele ma ka nohona kiwikā i loko o ka paukūʻolokaʻa;
2) mīkini'opihia - nā kiwikā Hoopaa iho la;
3) mapuna - ka pahū'ā o ka combustible hui;
4) a no ka maluhiluhi - hoʻokuʻu kinoea a no ka maluhiluhi i loko o ka lewa.

mahu mīkini peahi uila

Ka mahu mīkini peahi uila ka ikehu huli ana ia lŘlŘ aie i ke koena unuhi o ka wai mahu malihini ma ka muliwai a me ka mākeke.
Power o kēia mahu turbines hiki 1,300 MW.

Kekahi oaoieei-kiko'î o ka mahu mīkini peahi uila 1.200 MW

• Mahu puʻe (hou) - kŰkelŰ 23.5 MPa.
• Mahu mahana - 540 ° C.
• Mahu pele mīkini peahi uila - 3600 m / h.
• Epaepa huila mämä holo - 3000 rev / min.
• Ka mahu puʻe i loko o ka condenser - 3,6 kPa.
• mīkini peahi uila Length - 47,9 m.
• Mass mīkini peahi uila - 1900 m.

Thermal mīkini ninoieo o ka lewa mea'opihia, combustor a me ke kinoea mīkini peahi uila. Hana: adiabatically ea ua omo ai i loko o ka mea'opihia, no laila kona wela ua hoalaia mai i ka 200 ° C a oi. Next, ka'opihia lewa komo i ka'ā maluna, i kahi kiʻekiʻe puʻe ka poʻe lako wai a wahie - kerosene photogen wahie aila. Iloko o ke'ā o ka lewa wahie enaena i ka wela o 1500-2000 ° C, ia Hoʻonui i ka pono a me ka maoli kona māmā holo. Ka lewa neiʻoniʻoni ma kiʻekiʻe wikiwiki, a me ka'ā nā huahana i kauohaia i loko o ka mīkini peahi uila. Ma hope o ka hoʻololi mai kahua i kahua'ā mīkini peahi uila kōmi 'ana i kona kinetic ikehu. Part o ka ikehu i loaa mai ma ka mīkini peahi uila o ka mea'opihia kuapo; hapa ka i koe, ua hoopauia ma ka mīkini hana wāwahie epaepa huila, epaepa huila mokulele a me ka meaola moku, he kaa huila.

Ke kinoea mīkini peahi uila hiki ke hoʻohana ', he okoa ka rotational pelane, a me nā huila a kaa propellers o ka moku, e like me ka mokulele hēkī engine. Air, a'ā kinoea i kipaku i kiʻekiʻe māmā holo, mai ke kinoea mīkini peahi uila, pela ka mokulele hēkī hookomo i kupu i loko o kēia kaʻina hana paha e hoʻohana i ka hoʻoneʻe mokulele (mokulele) a me ka wai (moku) moku, alahao amo. No ka laʻana, turboprop kiko'ī i Kekoa HE-24, HE-124 ( "Ruslan"), RU-225 ( "Dream"). Ke'ī mai, ka "Dream" ma ka holo māmā holo o 700-850 km / h mea hiki ke hali ana i 250 na tona o ka ukana ma luna o ka mamao o aneane 15,000 kilomika. He ka nui loa amo mokulele i loko o ke ao nei.

? Aneie pilikia o thermal machines

Great hopena ma ke aniau o ka lewa rula, pakahi aku la ia i ke alo o ke kalapona'okikene lua a me ka wai ka ohu. Ke'ī mai, i ka loli ma o carbon dioxide maʻiʻo hiki aku ai i ka mahuahua ana a me ka emi ana ma ka hoʻomehana honua, i loko o a o carbon dioxide absorbs kekahi o ka wela e Pāhawewe i loko o ka honua a puni, hoʻopaneʻe 'ia ana i loko o ka lewa, piʻi pū, a pela i kaʻilikai mahana, a me ka lalo lewa. Radio ke kŰia o ka hoʻomehana honua heʻano nui kūlana i loko o ka huliau mitigation. I kona wa e kaawale aku, o kaʻawelike o ka Honua makemake ole +15 ° C, a malalo e 30-40 ° C.

i loko o ke ao nei he mea e oi aku mamua o 300 miliona acee? iuo oeiia o kaa, a ho okumu oi ma mua o ka hapalua o nā mea a pau ea haumia ea.

Over 1 makahiki i loko o ka lewa, mai ka thermal ka mana mai ke'ā o ka wahie ua anao? Aou 150 miliona na tona o ka luaipele oxides, 50 miliona na tona o ka naikokene'okesaside, 50 miliona na tona o ka lehu, 200 miliona na tona o ka kalapona monoxide, 3 miliona tons Feona.

I ka haku mele 'ana o ka lewa kikowaena'okikene kolu, a i malama a pau ke ola ma ka honua a pau, mai o ka waiwaiʻino wale i o ultraviolet kukuna. , I ka 1982, John Farman, kaʻImi Loa Beritania, i loaaʻi ma Antarctica'okikene kolu puka - he pokole ka ho'ēmiʻana o ka'okikene kolu maʻiʻo i loko o ka lewa. Ma ka piko o ka'okikene kolu lua 7 October 1987 i ka nui o ka'okikene kolu i loko o ka mea ua ua hoʻemi i loko o 2 manawa. 'okikene kolu puka paha kūpono mai anthropogenic aʻe, a me hoʻohana ma o ka hana o ka chlorine-i loaʻa ka freons (CFC), a luku i ka'okikene kolu, ahu iho. Naʻe, i ka makahiki 1990 study. i hookupaa iho la ia i kēia nānaina. Loa paha, i ka muli o ka'okikene kolu lua mea,ʻaʻole i hōʻikeʻia ke kanaka hana, a me ka mea he kūlohelohe kaʻina. I ka makahiki 1992, i ka'okikene kolu puka i loaa ma ka Arctic.

Ināʻohi i ka lewapuni'okikene kolu, ahu iho i loko o ka Honua i ka ili, a hanaʻia naʻe ia a hiki i ka pa apŘ o ka lewa ma ka lewa puʻe, a me ka wela o ka 0 ° C, laila'okikene kolu pale kaua mānoanoa mea wale 2-3 mm o! A i ka pau pale kaua.

A wahi o ka moolelo ...

• July 1769. Ma Paris Meudon pāka koa lunaʻenehana NZ Kyunyo ke "ahi hale", a i lako pono me ka mau-paukūʻolokaʻa mahu engine, hooauhee aku la i kekahi mau na umi o mika.
• 1885. Karl Benz, he Kelemānia lunaʻenehana, kukulu iho la i ka mua eha-huila kola kaʻa Motorwagen mana o 0.66 kW, a 29 January 1886 loaa i ka iaoaioa. Machine mämä holo ua 15-18 km / h.
• 1891. Gottlieb Daimler, he Kelemānia inventor, ua hanaʻia trolley kipaku mana 2,9 kW (4 horsepowers) o ke kaʻa. ʻO kā mākou ka mämä holo o ke kaa i kīnā 10 km / h, i ka 'auhau i loko o kaʻokoʻa Ke Ana Hoʻohālike mea mai ka 2 a hiki i 5 tona.
• 1899. Aaeuaeeneei K. Zhenattsi i loko o kona kaʻa, "Jamet Contant" ( "loa hoomaona mai la oia") no ka manawa mua i kela kapa o ka 100-kilomika laina holo.

Ano he kumu hoʻohālike o ka hoʻoponopono pilikia

Pilikia 1. Ka wela o ka iaia? Aaaoaeuiuo maikaʻi wela engine mea like i ka 2000 K, a me ka Pahu Hau mahana - 100 ° C. E hooholo i ka ka hoʻokōʻana.

pāʻoihana:
Ka haʻilula e hoʻoholo i ka ka hoʻokōʻana o ka wela engine (i kā mākou):

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

A: engine ka hoʻokōʻana - 81%.

Pilikia 2. Ka wela engine 200 kJ o ka wela i loaa mai ma ke'ā o ka wahie, a ua hoolilo i ka cooler 120 kJ wela. He aha mea ka ka hoʻokōʻana o ka engine?

pāʻoihana:
Ke haʻilula no ka hoomaopopo ana i ka ka hoʻokōʻana mea o ka palapala:

N = Q1 - Q2 / Q1.
N = (2 × 10 ⁵ J - 1,2 m 10 ⁵ J) / 2 m 10 ⁵ J = 0,4.

A: ka thermal ka hoʻokōʻana o ka engine - 40%.

Pilikia 3. He aha ka ka ka hoʻokōʻana o ka wela engine, ka wā ka hana loli mai ka iaia? Aaaoaeuiuo ma hope o ka loaa ana o ka nui o ka wela o ka 1,6 MJ hana hana 400 kJ? He aha ka i ka huina o ka wela i laila 'o ia i ka Pahu Hau?

pāʻoihana:
Ka hoʻokōʻana hiki ke nānā 'ia e ka haʻilula

N = A / Q _1.

N = 0,4 · 10 ⁶ J / 1,6 · 10 ⁶ J = 0,25.

Ho'īli Pahu Hau wela mea hiki ke nānā 'ia e ka haʻilula

Q ₁ - A = Q _2.
Q ₂ = 1.6 · 10 ⁶ J - 0,4 · 10 ⁶ J = 1,2 · 10 ⁶ J.
A: ka wela engine mai i ka hoʻokōʻana o ka 25%; ka nui o ka wela hoololiia a hiki i ka Pahu Hau - 1,2 · 10 ⁶ J.