Wind direction average calculation - AWS810

AWS810 System Description
Document code
M212417EN
Revision
H
ft:locale
en-US
Product
AWS810
Document type
Technical description

Wind direction average is calculated using the unit vector method.

The following formulas are used:

Formula 1

X S U M ⁢ = ∑ i = 1 n sin ( W ⁢ D i )

Formula 2

Y S U M ⁢ = ∑ i = 1 n cos ( W D i )

Formula 3

W D A ⁢ = atan 2 ⁢   ( X S U M , Y S U M )
Explanation of wind direction average calculation formulas
Item Explanation
WDi Wind direction
XSUM Sum of wind direction components parallel to X‑axis (East-West)
YSUM Sum of wind direction components parallel to Y‑axis (North-South)
WDA Wind direction average
Inputs for wind direction average calculation
Input Variable
Wind directions

List of wind directions:

  • For 3‑second average the measurements for the last 3 seconds
  • For longer averages the list of 3‑second averages from the time window