Sol-air temperature

Sol-air temperature (T_sol-air) is a variable used to calculate cooling load of a building and determine the total heat gain through exterior surfaces. It is an improvement over:

Where:

The above equation only takes into account the temperature differences and ignores two important parameters, being 1) solar radiative flux; and 2) infrared exchanges from the sky. The concept of T_sol-air was thus introduced to enable these parameters to be included within an improved calculation. The lower formula results:

${\displaystyle T_{\mathrm {sol-air} }=T_{o}+{\frac {(a\cdot I-\Delta Q_{ir})}{h_{o}}}}$

Where:

The product ${\displaystyle T_{\mathrm {sol-air} }}$ just found can now be used to calculate the amount of heat transfer per unit area, as below:

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