Kho qhov chaw Emissivity rau Infrared Thermometers
Infrared radiation yog ubiquitous thiab perpetual. Qhov sib txawv ntawm qhov kub ntau dua ntawm cov khoom, qhov ntau tshaj tawm cov nyhuv hluav taws xob. Los ntawm lub tshuab nqus tsev, lub zog infrared radiant emissions los ntawm lub hnub mus ncig 93 lab mais thoob plaws qhov chaw kom ncav cuag lub ntiaj teb, qhov chaw nws nqus thiab muab kev sov so. Thaum sawv ntsug ntawm lub tub yees tso rau hauv cov khw muag khoom, cov cua sov los ntawm cov hluav taws xob infrared tawm los ntawm peb lub cev yog absorbed los ntawm cov zaub mov txias, tsim kom muaj qhov sib txawv txias txias. Ob qho piv txwv no qhia pom tseeb hluav taws xob
cov teebmeem, tso cai rau peb kom pom meej qhov kev hloov pauv thiab muaj nyob ntawm cov hluav taws xob infrared.
Txhawm rau ntsuas qhov cuam tshuam ntawm cov hluav taws xob infrared, nws yog ib qho tsim nyog los ntsuas qhov kub ntawm hluav taws xob, uas siv cov ntsuas kub infrared. Cov ntaub ntawv sib txawv muaj cov yam ntxwv ntawm infrared tawg. Ua ntej yuav ntsuas qhov ntsuas kub nrog lub ntsuas kub infrared, nws yog ib qho tseem ceeb kom nkag siab txog cov hauv paus ntsiab lus ntawm kev ntsuas kub infrared thiab cov hluav taws xob hluav taws xob ntawm cov khoom ntsuas.
Infrared Radiance=Absorptivity + Reflectivity + Transmissivity
Tag nrho cov hluav taws xob infrared yog absorbed raws li emission, yog li ntawd absorptivity sib npaug emissivity. Cov ntsuas kub infrared ntsuas tsuas yog lub zog hluav taws xob tawm los ntawm cov khoom nto thiab tsis tuaj yeem ntes lub zog infrared dissipated hauv huab cua. Rau kev ntsuas ntsuas, kev xa tawm tuaj yeem raug tsis saib xyuas, ua rau cov qauv tseem ceeb rau ntsuas kub infrared:
Emissivity=1 - Reflectivity
Reflectivity yog inversely proportional rau emissivity. Qhov muaj zog ntawm cov khoom muaj peev xwm los cuam tshuam cov hluav taws xob infrared, qhov tsis muaj zog nws lub peev xwm los tawm cov hluav taws xob infrared. Reflectivity tuaj yeem kwv yees kwv yees los ntawm kev tshuaj xyuas qhov muag. Polished tshiab tooj liab muaj siab reflectivity thiab tsawg emissivity (0.07-0.2), thaum oxidized tooj liab nta tsis tshua muaj reflectivity thiab siab emissivity (0.6-0.7). Hnyav heev tarnished thiab blackened tooj liab muaj ib tug txawm tsawg reflectivity nrog ib tug correspondingly siab emissivity ntawm 0.88. Feem ntau cov xim pleev xim muaj lub siab emissivity ntawm 0.9-0.95, nrog negligible reflectivity.
Rau feem ntau cov ntsuas kub infrared, qhov tseem ceeb ntawm kev teeb tsa yog tus qauv emissivity tus nqi ntawm cov khoom ntsuas, uas yog lub Hoobkas preset rau 0.95. Qhov kev teeb tsa ua ntej no txaus rau ntsuas cov khoom siv organic thiab cov xim pleev xim.
Kho qhov teeb tsa emissivity ntawm tus pas ntsuas kub them nyiaj rau lub zog tsis txaus ntawm cov khoom siv, tshwj xeeb yog hlau. Qhov cuam tshuam ntawm kev cuam tshuam ntawm kev ntsuas qhov tseeb tsuas yog yuav tsum tau txiav txim siab thaum qhov kub kub infrared hluav taws xob muaj nyob ze ntawm qhov ntsuas thiab ua rau muaj kev cuam tshuam.
