Campbell CR800 Series - Calculations

Section 7. Installation
204
7.7.9.2.2 Calculations
Input Sample Vectors
FIGURE 46: Input Sample Vectors
In figure Input Sample Vectors (p. 204), the short, head-to-tail vectors are the input
sample vectors described by s
i
and Θ
i
, the sample speed and direction, or by Ue
i
and Un
i
, the east and north components of the sample vector. At the end of data
storage interval T, the sum of the sample vectors is described by a vector of
magnitude U and direction Θu. If the input sample interval is t, the number of
samples in data storage interval T is N = T / t. The mean vector magnitude is Ū =
U / N.
Scalar mean horizontal wind speed, S:
where in the case of orthogonal sensors:
Unit vector mean wind direction,
where