Measuring nonextensitivity parameters in a turbulent Couette-Taylor flow -art. no. 035303

We investigate probability density functions of velocity differences at dif ferent distances r measured in a Couette-Taylor flow for a range of Reynold s numbers Re. There is good agreement with the predictions of a theoretical model based on nonextensive statistical mechanics (where the entropies are nonadditive for independent subsystems). We extract the scale-dependent no nextensitivity parameter q(r,Re) from the laboratory data.