MILLER, P. L. & DIMOTAKIS, P. E. 1991 "Stochastic geometric properties of scalar interfaces in turbulent jets," Phys. Fluids A 3,168-177.


Experiments were conducted in which the behavior of scalar interfaces in turbulent jets was examined, using laser-induced fluorescence (LIF) techniques The experiments were carried out in a high Schmidt number fluid (water), on the jet centerline, over a jet Reynolds number range of l000<=Re<=24 000 Both two-dimensional scalar data, c(r, t) at fixed x/d, and one-dimensional scalar data, c(t) at fixed x/d and r/x, were analyzed using standard one- and two-dimensional fractal box-counting algorithms. Careful treatment was given to the handling of noise. Both long and short records as well as off-centerline measurements were also investigated. The important effect of threshold upon the results is discussed. No evidence was found of a constant (power-law) fractal dimension over the range of Reynolds numbers studied. On the other hand, the results are consistent with the computed behavior of a simple stochastic model of interface geometry.