Scaling of mixed longitudinal velocity-temperature structure functions

Measurements in a turbulent round jet at a moderately high Taylor microscal e Reynolds number R-lambda indicate that the mixed structure functions of u , the longitudinal velocity fluctuation, and theta, the temperature fluctua tion, show a smaller departure from the Kolmogorov (1941)-Obukhov (1949) sc aling than either the velocity or temperature structure functions at the sa me order. This reduced anomalous scaling indicates that the velocity and te mperature increments are not statistically independent, as is reflected by the non-negligible correlation between velocity and temperature increments. The scaling exponents of both the temperature structure functions and the mixed u-theta structure functions increase with R-lambda.