Analysis of the 



It was decided in the present instance to employ an equation of the form 



'V 



i =*. 



This represents a rectangular hyperbola connecting the anemometer factor V/v with the true 

 wind velocity V. Both the constants h and k are non-dimensional and it must therefore be possible 

 to describe them with a finite number of non-dimensional parameters of the constants of the 

 particular instrument. It is immediately evident that as F—xx>, V/v tends to the asymptote h, 



thus 



h = (V/v) v ^ = K/Lb, (K = 5280/2*- for Marvin's units*) 



where b is Marvin's asymptotic value of N, and 



h m- 



k = -{a+V )= — 



These expressions for h and k give their relation to Marvin's constants a and b. An example of the 

 hyperbolic law fitted to experimental calibration points is shown in Fig. 1. 



a - 



1 2 S 4 5 S 7 



Fig. 1 



a 9 



In the following, all quantities are expressed throughout in meters and meters per second. 



