Method of estimation of turbulence characteristic scales

Abstract

We propose an optical method that uses phase data of a laser beam obtained from a Shack-Hartmann sensor to estimate both the inner and outer scales of turbulence. The method is based on the sequential analysis of normalized correlation functions of Zernike coefficients. It allows the exclusion C(n)(2) from the analysis and reduces the solution of a two-parameter problem to a sequential solution of two single-parameter problems. The method has been applied to estimate the outer and inner scales of turbulence induced in the water cell.

Thread-shaped intensity field after light propagation through the convective cell

“…The obtained estimation of the inner scale was in a good agreement with estimations obtained by using phase measurements in the convective cell [27]. Note that the inner scale and as well as the outer scale is needed to describe phase distortions [27].…”

“…We study the problem of description of light propagation through a convective water cell based on spectral description of turbulence. In this Latter we show that two- Convective cell is described in details in [27] and contains two horizontal plates: the lower heating plate and upper cooling plate which are held at constant temperatures. Turbulence has been induced with a vertical temperature gradient between plates.…”

“…Though convection cells have been used previously to study light propagation in turbulent media [28], [10] and to estimate turbulent characteristics [29], [27] plume structures have not been considered and discussed.…”

Effects of Turbulent Environment on Self-Organized Critical Behavior: Isotropy vs. Anisotropy

“…From physics viewpoints, the parameter m has the meaning of the inverse integral (outer) turbulence scale: m ∼ L −1 . In laboratory or atmospheric turbulence L, the largest scale in the problem, can be estimated as 1 ÷ 100 m; see, e.g., [57][58][59]. The precise form of the IR regularization is unimportant, because the critical dimensions we are interested in here do not depend on its choice [3].…”

Effects of turbulent environment on self-organized critical behavior: Isotropy vs Anisotropy

“…From physics viewpoints, the parameter m has the meaning of the inverse integral (outer) turbulence scale: m ∼ L −1 . In laboratory or atmospheric turbulence L, the largest scale in the problem, can be estimated as 1 ÷ 100 m; see, e.g., [57][58][59]. The precise form of the IR regularization is unimportant, because the critical dimensions we are interested in here do 1 Traditionally, the nonlinear term ∂ h 2 /2 has a coupling constant as a prefactor.…”