Scaling of mixed longitudinal-transverse velocity structure functionsG. Xu1, R. A. Antonia2 and S. Rajagopalan2
1 School of Civil Engineering, University of Sydney - NSW 2006, Australia
2 Discipline of Mechanical Engineering, University of Newcastle - NSW 2308, Australia
received 6 March 2007; accepted in final form 3 July 2007; published August 2007
published online 26 July 2007
Measurements in a turbulent round jet at a Taylor microscale Reynolds number of about 500 indicate that the mixed structure functions of u, the longitudinal velocity fluctuation, and v, the transverse velocity fluctuation, show a larger departure from the Kolmogorov scaling than the u structure functions, and a smaller departure than the v structure functions. Although the scaling exponents of the temperature structure functions are nearly equal to those of the v structure functions at a comparable order, the mixed structure functions of u and the temperature fluctuation exhibits a smaller departure from the Kolmogorov scaling than either u or structure functions at the same order. The difference between the scaling behaviour of these two mixed structure functions mainly reflects the difference in correlation between and either or , implying that there is an important difference between temperature and velocity fields.
47.27.wg - Turbulent jets.
47.27.-i - Turbulent flows.
© Europhysics Letters Association 2007