Comparison between high-order velocity vector and temperature structure functions

A previously established similarity between the second-order temperature structure function, [(delta theta)(2)], and the sum of the second-order velocity structure functions, [(delta p)(2)], is extended to higher-order moments. Measurements in a low Reynolds number turbulent wake indicate that [\delta theta*\(n)], for n=2 to 6, is in much closer agreement with [\delta q*\(n)] than with [\delta u*\(n)], where u is the longitudinal velocity fluctuation and asterisks denote normalization by Kolmogorov scales. The behavior of [\delta q*\(4)] and [\delta theta*\(4)] at small separations is consistent with isotropy.