arXiv subjects

R. Tripiccione

Publications and source records attributed to R. Tripiccione.

60 records · Page 4Linked to original sources

arXiv1996

(1+1)-dimensional turbulence

A class of dynamical models of turbulence living on a one-dimensional dyadic-tree structure is introduced and studied. The models are obtained as a natural generalization of the popular GOY shell model of turbulence. These models are found to be chaotic and intermittent. They represent the first example of (1+1)-dimensional dynamical systems possessing non trivial multifractal properties. The dyadic structure allows to study spatial and temporal fluctuations. Energy dissipation statistics and its scaling properties are studied. Refined Kolmogorov Hypothesis is found to hold.

chao-dyn↗

arXiv1995

Generalized scaling in fully developed turbulence

In this paper we report numerical and experimental results on the scaling properties of the velocity turbulent fields in several flows. The limits of a new form of scaling, named Extended Self Similarity(ESS), are discussed. We show that, when a mean shear is absent, the self scaling exponents are universal and they do not depend on the specific flow (3D homogeneous turbulence, thermal convection , MHD). In contrast, ESS is not observed when a strong shear is present. We propose a generalized version of self scaling which extends down to the smallest resolvable scales even in cases where ESS is not present. This new scaling is checked in several laboratory and numerical experiment. A possible theoretical interpretation is also proposed. A synthetic turbulent signal having most of the properties of a real one has been generated.

chao-dyn↗

arXiv1995

Extended Self Similarity in numerical simulations of 3D anisotropic turbulence

Using a code based on the Lattice Boltzmann Equation, we have performed numerical simulations of a turbulent shear flow. We investigate the scaling behaviour of the structure functions in presence of anisotropic homogeneous turbulence, and we show that although Extended Self Similarity does not hold when strong shear effects are present, a more generalized scaling law can still be defined.

chao-dyn↗

arXiv1995

A new scaling property of turbulent flows

We discuss a possible theoretical interpretation of the self scaling property of turbulent flows (Extended Self Similarity). Our interpretation predicts that, even in cases when ESS is not observed, a generalized self scaling, must be observed. This prediction is checked on a number of laboratory experiments and direct numerical simulations.

chao-dyn↗

arXiv1995

On the intermittent energy transfer at viscous scales in turbulent flows

In this letter we present numerical and experimental results on the scaling properties of velocity turbulent fields in the range of scales where viscous effects are acting. A generalized version of Extended Self Similarity capable of describing scaling laws of the velocity structure functions down to the smallest resolvable scales is introduced. Our findings suggest the absence of any sharp viscous cutoff in the intermittent transfer of energy.

chao-dyn↗

arXiv1994

Polyakov Loops and Finite-Size Effects of Hadron Masses in Lattice Full Q.C.D

The polarization of Polyakov type loops is responsible for the difference between quenched and unquenched finite size effects on the QCD mass spectrum. With a numerical simulation, using different sea quarks boundary conditions, we show that we can align the spatial Polyakov loops in a predefined direction. Starting from these results, we propose a procedure to partially remove the Polyakov type contributions in the meson propagators.

hep-lat↗