Introduction to Modern Wind Turbines - Wind Turbine Technology: Fundamental Concepts of Wind Turbine Engineering - page 83

Figure 2-19. Calculated variation of coeficients of energy with wind speed for current
representative large- and small-scale wind turbines, compared with coeficients of two
early prototype wind turbines.
where
M = subscript denoting model parameters
Unfortunately, the Reynolds Number (aerodynamic parameter proportional to the product of
the resultant wind speed and a characteristic length such as the rotor radius) of the model will
be signiicantly smaller than that of the full-scale rotor, by the ratio R M /R. This may affect
the lift and drag characteristics of the model blades.