Silica Cib Thermal Conductivity

(1) Kev cuam tshuam ntawm porosity ntawm thermal conductivity.
Nws feem ntau lees paub tias cov thermal conductivity ntawm cov pa roj tsawg tsawg dua li cov khib nyiab. Lub siab porosity ntawm cov ntaub ntawv rwb thaiv tsev zoo thaiv cov cua sov hloov thiab ua kom muaj txiaj ntsig zoo los txo cov thermal conductivity ntawm cov khoom. Porosity plays lub luag haujlwm tseem ceeb hauv thermal rwb thaiv tsev ntawm cov khoom. Qhov siab dua qhov porosity, qhov me dua qhov chaw nyob ntawm phab ntsa pore thiab qis dua thermal conductivity. Tab sis muaj kev txwv rau qhov nce ntawm porosity. Yog tias cov porosity siab dhau lawm, cov ntsiab lus ntawm tib lub ntim ntawm cov cua sov-insulating refractory bricks tsawg dua, thiab cov khoom siv ntawm cov khoom tsis zoo thiab tsis tuaj yeem ua tau raws li qhov yuav tsum tau siv.
Tsis tas li ntawd, qhov xwm txheej ntawm qhov pores muaj qhov cuam tshuam zoo rau cov thermal conductivity ntawm cov khoom. Nyob rau hauv tib qhov ntom ntom, siab qhib porosity thiab txuas porosity refrastory recractory muaj ntau dua thermal envosity.

(2) Cov nyhuv ntawm qhov pore loj ntawm thermal conductivity ntawm thermal rwb thaiv tsev cov ntaub ntawv.
Thaum lub porosity yog qhov tseeb, qhov me me ntawm qhov pore loj, qhov qis dua thermal conductivity, qhov zoo dua thermal rwb thaiv tsev kev ua tau zoo. Qhov no yog vim hais tias, nyob rau tib lub porosity, yog hais tias lub pore loj nyob rau hauv cov khoom yog me me, tus naj npawb ntawm pores nyob rau hauv tib lub ntim ntawm cov khoom nce. Ntawm qhov tod tes, raws li qhov pore loj zuj zus, qhov txav ntawm cov roj molecules nyob rau hauv lub pores yog txwv thiab cov thermal convection nyob rau hauv lub pores txo, yog li cov thermal conductivity ntawm cov khoom ib txwm txo. Ntawm qhov tod tes, qhov nce ntawm cov qhov ua rau thaj tsam ntawm phab ntsa pore nyob rau hauv tib lub ntim, uas ua rau kom lub tshav kub hloov lwm lub tsev deb ntawm cov khoom theem, nws prolongs lub tshav kub hloov lub sij hawm thiab txo cov thermal conductivity ntawm cov khoom. Thaum qhov pore loj dua 0.1, thermal conductivity ntawm cov khoom ua raws li Loeb qauv.
Thaum lub pore loj dua 1, lub thermal conductivity yog proportional rau lub voos xwmfab ntawm cov duab zoo, pore loj, hluav taws xob tas li, thermal emissivity thiab kub. Thaum qhov pore loj dua 0.1, qhov kev hloov ntawm thermal conductivity ntawm cov khoom yuav tsis ua raws li Loeb qauv. Yog tias qhov pore loj me me li 50 nm, kev txav ntawm cov roj molecules yuav raug txwv, thiab tsis muaj kev txav mus los lawv yuav raug adsorbed rau ntawm phab ntsa pore thiab tsis muaj cua sov yuav tshwm sim.

(3) Cov nyhuv ntawm cov khoom theem ntawm thermal conductivity ntawm cov khoom.
Lub tshav kub hloov hom ntawm cov khoom theem ntawm cov khoom yog feem ntau conduction tshav kub hloov lwm lub tsev, uas yog, thermal co ntawm lub lattice. Yog hais tias lub thermal conductivity thiab kub muaj peev xwm ntawm raw cov ntaub ntawv me me, lub thermal rwb thaiv tsev muaj peev xwm ntawm refractory bricks yuav nce. 1000 degree hauv qab no, nrog rau qhov kub thiab txias, feem ntau ntawm thermal conductivity ntawm cov khoom yog feem ntau ib tug downward qauv; Nrog rau qhov kub siab tshaj 1000 degree, feem ntau ntawm cov thermal conductivity ntawm cov khoom yog ib qho kev nce siab. Tsis tas li ntawd, thermal conductivity ntawm non-oxides feem ntau yog siab dua li ntawm oxides, thiab ntawm oxides, thermal conductivity ntawm aluminosilicate cov ntaub ntawv yog tsawg tshaj li cov ntshiab oxide cov ntaub ntawv. Vim yog cov qauv ntawm cov lattice dav dav, kev faib tawm sab hauv ntawm atoms yog chaotic, lub tshav kub hloov mus qeeb, thiab thermal conductivity yog me me.