Hi, I don't know how to get the Greek symbols here, but here goes. Reynolds number = rho x v x l / mu. Assuming your wind tunnel is up to mark, rho, v, and mu will match the conditions for which you are testing the model. However, l (lower case of L) will differ (quite a bit) between the model and the actual aircraft. This leads to the 'scale effect'. A dose of AP 3456 (extremely basic stuff, don't worry) would help you as would the Prouty series. Good luck!
