Temperature formulas (Heat Overlay): Difference between revisions

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==Atmospheric Temperature formula==
==Atmospheric Temperature formula==
T<sub>a,t</sub> = T<sub>station,t</sub> + UHI<sub>max,t</sub> * f<sub>sun,t</sub><br>
T<sub>a,t</sub> = T<sub>station,t</sub> + UHI<sub>max,t</sub> · f<sub>sun,t</sub><br>
where,
where,
* T<sub>a,t</sub> is the calculated [[Temperature_atmosphere_result_type_(Heat_Overlay)|atmospheric temperature]] at time t;
* T<sub>a,t</sub> is the calculated [[Temperature_atmosphere_result_type_(Heat_Overlay)|atmospheric temperature]] at time t;
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==Wet-bulb Temperature formula==
==Wet-bulb Temperature formula==
T<sub>w</sub> = T<sub>a</sub> * atan( 0.151977 * (ϕ + 8.313659)<sup>0.5</sup>) + atan (T<sub>a</sub> + ϕ) - atan(ϕ - 1.676331) + 0.00391838ϕ<sup>3/2</sup> atan(0.023101ϕ) - 4.686935<br>
T<sub>w</sub> = T<sub>a</sub> · atan( 0.151977 · (ϕ + 8.313659)<sup>0.5</sup>) + atan (T<sub>a</sub> + ϕ) - atan(ϕ - 1.676331) + 0.00391838 · ϕ<sup>3/2</sup> atan(0.023101 · ϕ) - 4.686935<br>


==See also==
==See also==
* [https://en.wikipedia.org/wiki/Wet-bulb_temperature| Wet-bulb temperature]
* [https://en.wikipedia.org/wiki/Wet-bulb_temperature| Wet-bulb temperature]

Revision as of 15:00, 11 September 2019

Two temperature formulas are used in the calculation of the PET value:

  • The atmospheric temperature Ta
  • The wet-bulb temperatur Tw

Atmospheric Temperature formula

Ta,t = Tstation,t + UHImax,t · fsun,t
where,

Wet-bulb Temperature formula

Tw = Ta · atan( 0.151977 · (ϕ + 8.313659)0.5) + atan (Ta + ϕ) - atan(ϕ - 1.676331) + 0.00391838 · ϕ3/2 atan(0.023101 · ϕ) - 4.686935

See also