Kaʻi lau waiwai o thermal conductivity o ka lewa

Joseph Black hoʻi i ka 1754 ma ua hoano e ia e nā hualoaʻa a maopopo i ka honua i ka lewa ( 'o ia hoʻi, ea) ninoieo o ka läÿau, he okoa kinoea, i ke kumu nui o ka i mea i oxygen a me ka naikokene. Ua i hoʻolauna i ka manaʻo e like me ke kaʻi lau waiwai o thermal conductivity o ka lewa.

All ola meaola ma ka honua, a hiki i ke ola ana o ka lewa ua koi, e aho, ea kulanui i - ka oxygen. Loko o oxygen'okesaside o ke komoʻana i ke kino, mai ka Ambient lewa, produces ikehu, me ka i, Aole e mau nō lā hoʻi o ke ola.

Oxygen ma ua hoʻomano hoʻohana 'ia ma ka hana a me kela la i keia ola - ua, kuu ae i'ā ana o ka wahie, a me na'ā kiko'ī - me mechanical ikehu. Ma kona liquefaction paka maikai kinoea.

I ka haku mele 'ana o ka lewapuni ea mai he nui hopena ma luna o nā ola a me ka ola o kēlā me kēia kanaka. Hemolele ( "pololei") ka haku mele 'ana kekahi i ka 75 pakeneka naikokene, 24 pakeneka oxygen, a me dala uuku o kekahi mau kinoea - methane, Neon, krypton, hydrogen, carbon dioxide i a me na mea e ae.

Loaʻa nui o hanalima-i? Iecaianoaaiiuo, o ka ulu helu o ke kaa a hoʻokuʻu akula i ka lewa miliona o liluwelo a me ka Nine Inch microparticles (aldehydes, ammonia, oxides, kaumaha i eliiaʻi) i loko, nunui hoʻohaumiaʻole ai i ka lewa, kahi o ka thermal conductivity o ka lewa ua hoemi, a he kūlana e loli ai i ka meaola e noho ana. Hoʻomehana honua, mai ka hana o ka ulia kaʻa kiko'ī (ia i loko o ka lewa o ka nui kulanakauhale ma ka liʻiliʻi 60 pakeneka) o ka loa nā palapala i ke kanaka kino. Lua o ka wahi no i thermal mana huahelu o ka haumia ea, a me ke kolu o ka i Nine Inch? Iecaianoaaiiuo.

Ke kumu waiwai o ka lewa o kona thermal conductivity. Kēia mau ho'āʻo ma lehulehu a me ka ike maopopo ana, ua hiki ke hooholo i ka wela i loko o ka gaseous meakino ua māhele i loko o ka papa kuhikuhiE aoao ekolu kānakaʻepekema: thermal pāhawewe (hawewe electromagnetic ka ikehu EYI), au paialewa (neʻe ikehu kahe ana ma kalepa papa o ke kinoea i loko o ka makahiki), thermal conductivity (kaulele neʻeʻana o nā lātoma ka paepaeʻana loaa wela mai ke kinoea, ahu iho me ka wela ma luna i emi "wela" papa o ke kinoea). Ma ke kaʻina hana o ka wela hoolilo nā lātoma i loaʻa hou ikehu pū i hiki kona nā lātoma me ka haʻahaʻa ikehu maʻiʻo. Ano hana e alakai i ka wela o ka physical aiao kaʻi lau waiwai o thermal conductivity o ka lewa. Kaʻi lau waiwai o thermal conductivity o ka lewa me ka nānā 'ia ma ka helu kaulike.

λ = -d2Qt / gt / gn * dF * dt.

Kaʻi lau waiwai o thermal conductivity o ka lewa ka heluna hapauuku like me ka nui o ka wela e hele no pa alima manawa au ma isothermal surfaces me concomitant ano ka wā gradt = 1. Kona kokoke dimensional waiwai ua manao me ka lākiō / (m · K) W.

Ka hopena o ka ho'āʻo a me ka ike maopopo ana i hana mai i ka Lookup papa, no ka mea, i oe ke hoʻoholo i nā aiee o ka thermal conductivity o ka lewa a me nā waiwai. No ka hapanui o 'ona, i ka wela hoolilo kaʻi lau waiwai hiki ke poe like me ka laina kuleana pili i

λ = λ0 * [1 + b. * (, t-e)],

kahi λ0 o ka waiwai o ke kaʻi lau waiwai, e hana ma ka thermal conductivity ma t0 = 0 kekelē Kelekia ma;

b. - a eia i manao experimentally.

Poʻe hewa nui o nā mea a pau hoʻomaka wela kinoea. Ke kaʻi lau waiwai o ka wela hoolilo kinoea, piʻi pū me ka mahuahua ana wela a me ka mea 0,006 ÷ 0,6 W / (m · K), kahi o ka luna waiwai, no helium a me ka hydrogen. Lākou koke thermal conductivity i ka elima paha heʻumi manawa oi aku ia o nā kinoea. Heat hoolilo kaʻi lau waiwai o ka lewa ma Aʻohe kekelē Kelekia ma ka 0,0243 W / (m · K).

I ka nui o ka wela lawe ia e ke kinoea papa i loko o ka wela kūkaʻi kaʻina hana, ina koe kŰlń iloko o ka manawa wā mawaena hoʻoholo ma ka luawai-ike Fourier kānāwai nä känaka 'epekema i ke ana wela like.