Combustible fakangatangata ʻo e kasa

ʻI he ngaahi tuʻunga angamaheni ʻo e sivi, ʻa e fakangatangata ʻo e tokanga ʻa ia ʻoku ʻi ai ha kasa combustible pe kakapu ʻoku fio ʻaki ha kasa oxidizing ʻoku ui ia ko e fakangatangata ʻo e fakaʻauha. Angamaheni ʻaki, ʻa e foʻi lea ko e ʻ fakangatangata ʻo e fakaʻauha’ ʻuhinga ki he ngaahi fakangatangata ʻo e ngaahi kasa combustible pe ʻahu ʻi he ʻea. Ko e tuʻunga maʻulalo taha ʻo ha kasa combustible te ne lava ʻo fakatupu ha fakaʻauha ʻoku ʻiloa ia ko e fakangatangata ʻo e fakaʻauha (LEL), pea mo e tokanga maʻolunga taha ʻo hange ko e fakangatangata ʻo e fakaʻauha ʻi ʻolunga (UEL).

ʻI he taimi ʻoku combustible ai ʻa e ngaahi kasa pe huhuʻa ʻahu ʻi he ngaahi fakangatangata ʻo e fakaʻauha pea fetaulaki mo ha maʻuʻanga vela (hange ko ha ulo ʻoku ava pe maʻolunga mafana ʻo e ʻea), ʻOku mafola vave ʻa e ulo ʻi he kasa pe efu. ʻOku hanga ʻe he tali vave ko ʻeni ʻo e kemikale ʻo tukuange ha vela lahi, faʻu ha ngaahi kasa ʻoku mafola koeʻuhi ko e vela, fakatupu ha mafana mo ha ngaahi faingataʻa lahi ʻe malava ke fakatupu ʻauha.

Ko e ngaahi fakangatangata ʻo e fakaʻauha ko ha ngaahi fakangatangata mahuʻinga ia ʻi hono fakamatalaʻi e ngaahi fakatuʻutamaki ʻo e velangofua ngaahi kasa, ʻahu, mo combustible efu. ʻI he angamahení, ʻOku fakahaaʻi ʻa e ngaahi fakangatangata ʻo e ngaahi kasa mo e ʻahu velangofua ko ha peseti ʻo e kasa pe mao ʻi he fefiofi.

Hange ko ʻeni, ʻi he 20 ° c, ʻa e founga ʻo e ului ki he volumetric siʻisiʻi mo e tokanga ʻa ha kasa ʻoku velangofua:

Y = (L/100) × (1000M/22.4) × (273/(273+20)) = L × (M/2.4)

ʻI he founga ko ʻeni, L ko e konga siʻi volumetric (%), Ko Y ʻa e tokanga lahi (g/m³), Ko e M ko e kainga molecular ia ʻo e combustible kasa pe kakapu, mo e 22.4 ko e leʻo lahí (lita ʻe) nofoʻi ʻe 1 mol ʻo ha koloa ʻi gaseous tuʻunga angamaheni (0° C, 1 atm).

Hange ko ʻeni, Kapau ʻoku tokanga ʻa e methane kasa ʻi he ʻatakai 10%, ko e kau papi ului ki he:

Y = L × (M/2.4) = 10 × (16/2.4) = 66.67 g/m³

Ko e foʻi fakakaukau ʻo e ngaahi fakangatangata ki he ngaahi kasa ʻoku velangofua, ʻahu, pea ʻe lava ke fakamatalaʻi ʻa e efu ʻaki ʻa e fakakaukau ki he fakaʻauha ʻo e thermal. Kapau ʻoku ʻi ai ha kasa ʻoku velangofua, ʻao ʻo e ʻao, pe ʻoku ʻi lalo ʻa e efu ʻi he LEL, koeʻuhi ko e fuʻu ʻea lahi, ʻa e ola mokomoko ʻo ʻo e ʻea, pea ʻikai feʻunga e tokanga ʻa e combustible, ʻOku mole lahi ange ʻa e vela ʻa e polokalama ʻi he meʻa ʻoku ne maʻu, pea ʻoku ʻikai hoko atu ʻa e tali. Ko e meʻa tatau pe, Kapau ʻoku maʻolunga ange ʻa e tokanga ʻi he UEL, ʻOku siʻisiʻi ange ʻa e vela ʻa e ʻea ʻi he mole ʻa e ʻea, fakaʻehiʻehi mei he tali. ʻIkai ngata ai, fuʻu lahi combustible kasa pe efu ʻoku ʻikai ngata pe ʻi he ʻikai ke ne lava ʻo tali mo fakatupu ha vela koeʻuhi ko e siʻisiʻi ʻa e ʻosikena ka ʻoku toe cools foki mo e fefiofi, fakaʻehiʻehi mei he mafola ʻa e ulo. ʻIkai ngata ai, ki ha ngaahi meʻa pau hange ko ethylene oxide, nitroglycerin, mo combustible efu hange ko gunpowder, ʻe lava ke aʻu ʻa e UEL 100%. ʻOku ʻomi ʻe he ngaahi naunau ko ʻeni ʻenau ʻosikena lolotonga decomposition, fakaʻata ʻa e tali ke hokohoko atu. ʻOku hanga ʻe he lahi ange ʻa e teke mo e mafana ʻo fakafaingofuaʻi ʻenau decomposition mo e fakaʻauha.