Diffuse radiation formula (Heat Overlay): Difference between revisions
No edit summary |
|||
| Line 24: | Line 24: | ||
|<math>\tau_a >= 0.7</math> | |<math>\tau_a >= 0.7</math> | ||
|} | |} | ||
where <math>\tau_a</math> is the atmospheric transmissivity. This is calculated as: | where <math>\tau_a</math> is the atmospheric transmissivity. This is calculated as: | ||
<math>\tau_{a} = \frac{Q_{gl,t}}{1367 \cdot \sin(\phi_t)}</math> | <math>\tau_{a} = \frac{Q_{gl,t}}{1367 \cdot \sin(\phi_t)}</math> | ||
Revision as of 14:19, 23 September 2019
The diffuse radiation is an input parameter for the PET-formula.
The diffuse radation Qd at time t is calculated using the following formula:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle Q_{d,t} = Q_{gl,t} \cdot f_{transmission,t}}
where,
- is the amount of sun radiation at time t, measured at a weather station.
- is the atmospheric transmission factor at time t.
Atmospheric transmission factor
The atmospheric transmission factor ftransmission,t is calculated as followed:
| ftransmission,t | Condition |
|---|---|
| Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 1} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tau_a < 0.3} |
| Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 1.6 - 2 \cdot \tau_a} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 0.3 < \tau_a < 0.7} |
| Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 0.2} | Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tau_a >= 0.7} |
where Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tau_a} is the atmospheric transmissivity. This is calculated as:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \tau_{a} = \frac{Q_{gl,t}}{1367 \cdot \sin(\phi_t)}}
where,
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle Q_{gl,t}} is the amount of sun radiation at time t, measured at a weather station.
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \phi_{t}} is the sun altitude angle in ° at time t.
