Kho qhov emissivity ntawm tus pas ntsuas kub infrared
Cov hluav taws xob infrared yog ubiquitous thiab tsis kawg, thiab ntau dua qhov kub ntawm qhov sib txawv ntawm cov khoom, lub suab nrov tshaj qhov tshwm sim tshwm sim. Lub tshuab nqus tsev tuaj yeem xa cov hluav taws xob hluav taws xob hluav taws xob tawm los ntawm lub hnub mus txog 93 lab mais ntawm lub sijhawm thiab qhov chaw rau lub ntiaj teb, qhov twg nws nqus los ntawm peb thiab ua rau peb sov siab. Thaum peb sawv ntsug ntawm lub tub yees khoom noj hauv lub khw, cov hluav taws xob hluav taws xob infrared uas tawm los ntawm peb lub cev yog nqus los ntawm cov khoom noj tub yees, ua rau peb txias heev. Cov nyhuv hluav taws xob yog qhov pom tseeb hauv ob qho piv txwv, thiab peb tuaj yeem hnov qhov kev hloov pauv thiab xav tias nws muaj nyob.
Thaum peb yuav tsum ntsuas qhov cuam tshuam ntawm cov hluav taws xob infrared, peb yuav tsum ntsuas qhov kub ntawm cov hluav taws xob infrared, uas yuav tsum tau siv lub ntsuas kub infrared. Cov khoom sib txawv muaj cov yam ntxwv sib txawv infrared tawg. Ua ntej siv lub ntsuas kub infrared los nyeem qhov kub thiab txias, peb yuav tsum nkag siab cov ntsiab lus tseem ceeb ntawm kev ntsuas hluav taws xob hluav taws xob thiab cov yam ntxwv tshwj xeeb ntawm hluav taws xob hluav taws xob ntawm cov khoom ntsuas.
Infrared emissivity =absorption rate+reflectance+transmittance
Txawm li cas los xij ntawm cov hluav taws xob infrared, ib zaug tso tawm, nws yuav raug nqus, yog li kev nqus tus nqi =emissivity. Tus pas ntsuas kub infrared nyeem cov hluav taws xob hluav taws xob infrared tawm ntawm qhov chaw ntawm qhov khoom. Lub tshuab hluav taws xob infrared tsis tuaj yeem nyeem cov hluav taws xob hluav taws xob infrared poob hauv huab cua. Yog li ntawd, hauv kev ntsuas kev ua haujlwm, peb tuaj yeem tsis quav ntsej qhov kev xa tawm. Ua li no, peb tau txais cov qauv yooj yim rau kev ntsuas hluav taws xob infrared:
Infrared emissivity =emissivity - reflectance
Reflectance yog inversely proportional rau emissivity, thiab qhov muaj zog ntawm cov khoom muaj peev xwm los cuam tshuam cov hluav taws xob infrared, qhov tsis muaj zog nws tus kheej muaj peev xwm los tawm cov hluav taws xob infrared. Feem ntau, kev tshuaj xyuas qhov muag yog siv los txiav txim siab qhov cuam tshuam ntawm ib qho khoom. Cov tooj liab tshiab muaj qhov cuam tshuam ntau dua tab sis qis emissivity (0.07-0.2), oxidized tooj liab muaj qhov qis dua tab sis siab dua emissivity (0.6-0.7), thiab tooj liab uas tig dub vim hnyav oxidation muaj txawm tias qis dua tab sis siab dua emissivity (0.88). Qhov emissivity ntawm feem ntau ntawm cov xim pleev xim yog siab heev (0.9-0.95), thaum lub reflectivity yuav tsis quav ntsej.
Rau feem ntau ntawm cov ntsuas kub infrared, qhov yuav tsum tau teeb tsa yog qhov ntsuas emissivity ntawm cov khoom kuaj, uas feem ntau yog pre-set rau 0.95. Qhov no txaus rau ntsuas cov khoom siv organic lossis pleev xim rau saum npoo.
Los ntawm kev kho cov emissivity ntawm tus pas ntsuas kub, qhov teeb meem ntawm tsis txaus infrared hluav taws xob hluav taws xob nyob rau saum npoo ntawm qee cov ntaub ntawv, tshwj xeeb tshaj yog cov ntaub ntawv hlau, tuaj yeem them rau. Tsuas yog thaum muaj qhov kub-kub infrared hluav taws xob nyob ze ntawm qhov chaw ntawm qhov khoom raug ntsuas thiab nws cuam tshuam, puas yog qhov cuam tshuam ntawm kev cuam tshuam ntawm qhov ntsuas yuav tsum xav txog.
