Tus nqi ntawm cov khoom rwb thaiv tsev thermal yog dab tsi?

Tus nqi U, tseem hu ua U-factor, yog ib qho kev ntsuas tseem ceeb hauv kev lag luam ntawm cov khoom siv rwb thaiv tsev. Nws sawv cev rau qhov nrawm uas cua sov kis tau los ntawm cov khoom siv. Tus nqi U qis dua, qhov ua tau zoo ntawm cov khoom rwb thaiv tsev zoo dua. Kev nkag siab txog tus nqi U ntawm cov khoom rwb thaiv tsev yog qhov tseem ceeb rau kev txiav txim siab txog kev siv hluav taws xob thiab kev nplij siab ntawm lub tsev.

Thaum xav txog cov khoom siv rwb thaiv tsev, nws yog ib qho tseem ceeb kom nkag siab txog nws tus nqi U kom ntsuas nws qhov ua tau zoo hauv kev tiv thaiv kev poob lossis nce cua sov. Qhov no yog qhov tseem ceeb tshwj xeeb hauv kev lag luam kev tsim kho, qhov twg kev siv hluav taws xob zoo thiab kev ruaj khov yog qhov tseem ceeb uas yuav tsum xav txog. Los ntawm kev xaiv cov khoom uas muaj tus nqi U qis dua, cov neeg ua vaj tse thiab cov tswv tsev tuaj yeem txo kev siv hluav taws xob thiab txo cov nqi cua sov thiab cua txias.

Tus nqi U ntawm cov khoom rwb thaiv tsev raug cuam tshuam los ntawm cov yam xws li hom khoom siv, tuab, thiab qhov ceev. Piv txwv li, cov khoom siv xws li fiberglass, cellulose, thiab ua npuas rwb thaiv tsev muaj cov nqi U sib txawv vim muaj cov thermal conductivities sib txawv. Tsis tas li ntawd, kev tsim kho thiab kev teeb tsa ntawm cov rwb thaiv tsev yuav cuam tshuam rau nws tus nqi U tag nrho.

Yuav kom txiav txim siab txog tus nqi U ntawm cov khoom siv rwb thaiv tsev tshwj xeeb, ib tus yuav tsum xa mus rau cov lus qhia tshwj xeeb uas cov chaw tsim khoom muab. Cov lus qhia no feem ntau suav nrog tus nqi U, uas qhia hauv cov chav ntawm W/m²K (Watts ib square meter ib Kelvin). Los ntawm kev sib piv cov nqi U ntawm cov khoom sib txawv, cov neeg siv khoom tuaj yeem ua qhov kev xaiv paub txog cov khoom siv rwb thaiv tsev twg zoo tshaj plaws rau lawv cov kev xav tau.

Hauv kev xaus, U-tus nqi ntawm cov khoom rwb thaiv tsev ua lub luag haujlwm tseem ceeb hauv kev ntsuam xyuas nws cov kev ua haujlwm thermal. Los ntawm kev nkag siab thiab xav txog U-tus nqi thaum xaiv cov ntaub ntawv rwb thaiv tsev, cov tib neeg thiab cov lag luam tuaj yeem pab txhawb kev txuag hluav taws xob thiab tsim kom muaj kev nyob thiab ua haujlwm zoo dua thiab ruaj khov. Nws yog ib qho tseem ceeb kom muab qhov tseem ceeb rau cov khoom uas muaj U-tus nqi qis dua rau kev siv hluav taws xob zoo tshaj plaws thiab kev nplij siab thermal.