492 citations · 3.8k across the 96 of their papers we have counts for
29 papers · 1 filter
Cumulative compressibility effects on population dynamics in turbulent flows
Prasad Perlekar, Roberto Benzi, David R. Nelson +1
Bacteria and plankton populations living in oceans and lakes reproduce and die under the in- fluence of turbulent currents. Turbulent transport interacts in a complex way with the…
Polymer Effects on Heat Transport in Laminar Boundary Layer Flow
Roberto Benzi, Emily S. C. Ching, Vivien W. S. Chu
We consider a laminar Blasius boundary-layer flow above a slightly heated horizontal plate and study the effect of polymer additives on the heat transport. We show that the action…
Heat transport by laminar boundary layer flow with polymers
Roberto Benzi, Emily S. C. Ching., Vivien W. S. Chu
Motivated by recent experimental observations, we consider a steady-state Prandtl-Blasius boundary layer flow with polymers above a slightly heated horizontal plate and study how t…
Stochastic Resonance in a simple model of magnetic reversals
Roberto Benzi, Jean-Francois Pinton
We discuss the effect of stochastic resonance in a simple model of magnetic reversals. The model exhibits statistically stationary solutions and bimodal distribution of the large s…
Fully developed turbulence and the multifractal conjecture
R. Benzi, L. Biferale
We review the Parisi-Frisch MultiFractal formalism for Navier--Stokes turbulence with particular emphasis on the issue of statistical fluctuations of the dissipative scale. We do i…
Universal intermittent properties of particle trajectories in highly turbulent flows
ICTR, :, A. Arneodo +27
We present a collection of eight data sets, from state-of-the-art experiments and numerical simulations on turbulent velocity statistics along particle trajectories obtained in dif…
Intermittency and Universality in Fully-Developed Inviscid and Weakly-Compressible Turbulent Flows
Roberto Benzi, Luca Biferale, Robert Fisher +3
We performed high resolution numerical simulations of homogenous and isotropic compressible turbulence, with an average 3D Mach number close to 0.3. We study the statistical proper…
Comparison of Theory and Direct Numerical Simulations of Drag Reduction by Rodlike Polymers in Turbulent Channel Flows
Roberto Benzi, Emily S. C. Ching, Elisabetta De Angelis +1
Numerical simulations of turbulent channel flows, with or without additives, are limited in the extent of the Reynolds number \Re and Deborah number \De. The comparison of such sim…
Stochastic Resonance: from climate to biology
Roberto Benzi
In this paper I will review some basic aspects of the mechanism of stochastic resonance. Stochastic resonance was first introduced as a possible mechanism to explain long term clim…
Numerical simulations of flow reversal in Rayleigh--Bénard convection
Roberto Benzi, Roberto Verzicco
We investigate numerically the statistical properties of the large scale flow in Rayleigh--Bénard convection. By using an external random perturbation on the temperature field, we…
Statistical Properties of Nonlinear Shell Models of Turbulence from Linear Advection Models: Rigorous Results
Roberto Benzi, Boris Levant, Itamar Procaccia +1
In a recent paper it was proposed that for some nonlinear shell models of turbulence one can construct a linear advection model for an auxiliary field such that the scaling exponen…
Mesoscopic modeling of a two-phase flow in the presence of boundaries: the Contact Angle
R. Benzi, L. Biferale, M. Sbragaglia +2
We present a mesoscopic model, based on the Boltzmann Equation, for the interaction between a solid wall and a non-ideal fluid. We present an analytic derivation of the contact ang…
On the Anomalous Scaling Exponents in Nonlinear Models of Turbulence
Luiza Angheluta, Roberto Benzi, Luca Biferale +2
We propose a new approach to the old-standing problem of the anomaly of the scaling exponents of nonlinear models of turbulence. We achieve this by constructing, for any given nonl…
Identification and Calculation of the Universal Maximum Drag Reduction Asymptote by Polymers in Wall Bounded Turbulence
Roberto Benzi, Elisabetta deAngelis, Victor S. L'vov +1
Drag reduction by polymers in wall turbulence is bounded from above by a universal maximal drag reduction (MDR) velocity profile that is a log-law, estimated experimentally by Virk…
Mesoscopic modeling of heterogeneous boundary conditions for microchannel flows
R. Benzi, L. Biferale, M. Sbragaglia +2
We present a mesoscopic model of the fluid-wall interactions for flows in microchannel geometries. We define a suitable implementation of the boundary conditions for a discrete ver…
Dynamical scaling and intermittency in shell models of turbulence
R. Benzi, L. Biferale, M. Sbragaglia
We introduce a model for the turbulent energy cascade aimed at studying the effect of dynamical scaling on intermittency. In particular, we show that by slowing down the energy tra…
Flow reversal in a simple dynamical model of turbulence
Roberto Benzi
In this paper, we study a simple hydrodynamical model showing abrupt flow reversals at random times. For a suitable range of parameters, we show that the dynamics of flow reversal…
A lattice Boltzmann study of non-hydrodynamic effects in shell models of turbulence
R. Benzi, L. Biferale, M. Sbragaglia +2
A lattice Boltzmann scheme simulating the dynamics of shell models of turbulence is developed. The influence of high order kinetic modes (ghosts) on the dissipative properties of t…
Saturation of Turbulent Drag Reduction in Dilute Polymer Solutions
Roberto Benzi, Victor S. L'vov, Itamar Procaccia +1
Drag reduction by polymers in turbulent wall-bounded flows exhibits universal and non-universal aspects. The universal maximal mean velocity profile was explained in a recent theor…
Shell Model of Two-dimensional Turbulence in Polymer Solutions
Roberto Benzi, Nizan Horesh, Itamar Procaccia
We address the effect of polymer additives on two dimensional turbulence, an issue that was studied recently in experiments and direct numerical simulations. We show that the same…
Stochastic Resonance in Two Dimensional Landau Ginzburg Equation
Roberto Benzi, Alfonso Sutera
We study the mechanism of stochastic resonance in a two dimensional Landau Ginzburg equation perturbed by a white noise. We shortly review how to renormalize the equation in order…
Intermittency in Turbulence: computing the scaling exponents in shell models
Roberto Benzi, Luca Biferale, Mauro Sbragaglia +1
We discuss a stochastic closure for the equation of motion satisfied by multi-scale correlation functions in the framework of shell models of turbulence. We give a systematic proce…
Theory of Concentration Dependence in Drag Reduction by Polymers and of the MDR asymptote
R. Benzi, E. S. C. Ching, N. Horesh +1
A simple model of the effect of polymer concentration on the amount of drag reduction in turbulence is presented, simulated and analyzed. The qualitative phase diagram of drag coef…
A Gibbs-like measure for single-time, multi-scale energy transfer in stochastic signals and Shell Model of turbulence
Roberto Benzi, Luca Biferale, Mauro Sbragaglia
A Gibbs-like approach for simultaneous multi-scale correlation functions in random, time-dependent, multiplicative processes for the turbulent energy cascade is investigated. We st…