A novel dimensionless parameter, the particle moment number Pa, was derived using dimensional analysis of the particle-laden Navier-Stokes equations, in order to understand the underlying physics of turbulence modification by particles. A set of 80 previous experimental measurements where the turbulent kinetic energy was modified by particles was examined, and all results could clearly be divid...

Some rigorous results connected with the conventional statistical theory of turbulence in both twoand three-dimensional cases are discussed. Such results are based on the concept of stationary statistical solution, related to the notion of ensemble average for turbulence in statistical equilibrium, and concern, in particular, the mean kinetic energy and enstrophy fluxes and their corresponding ...

We argue that the recently reported Kolmogorov-like magnetic turbulence spectrum in the cool core of the Hydra A galaxy cluster (Vogt & Enßlin 2005) can be understood by kinetic energy injection by active galaxies which drive a turbulent non-helical magnetic dynamo. We develop an analytical model of the turbulence in cool cores and show that it fits well to Faraday rotation magnetic field measu...

This Letter presents the first ab initio, fully electromagnetic, kinetic simulations of magnetized turbulence in a homogeneous, weakly collisional plasma at the scale of the ion Larmor radius (ion gyroscale). Magnetic- and electric-field energy spectra show a break at the ion gyroscale; the spectral slopes are consistent with scaling predictions for critically balanced turbulence of Alfvén wave...

Modeling the structure of molecular clouds depends upon good methods to statistically compare simulations with observations in order to constrain the models. Here we characterize a suite of hydrodynamical and magnetohydrodynamical (MHD) simulations of supersonic turbulence using an averaged wavelet transform, the ∆-variance, that has been successfully used to characterize observations. We find ...

Many processes interact in a complex and highly non-linear way during the life cycle of fog, the turbulent transport being among them. Observations and analysis of turbulence are, then, fundamental to our understanding of the physical mechanisms involved with fog formation, evolution and dissipation. Data gathered by fast-response sonic anemometers are processed using wavelet methods in order t...

Boundary conditions are the major obstacle in simulations based on advanced continuum models of rarefied and micro-flows of gases. In this paper we present a theory how to combine the regularized 13-moment-equations derived from Boltzmann’s equation with boundary conditions obtained from Maxwell’s kinetic accommodation model. While for the linear case these kinetic boundary conditions suffice, ...

Dissipation and flux-variance methods, derived from the turbulent kinetic energy and temperature variance budget equations in conjunction with Monin-Obukov similarity theory, were used to estimate surface fluxes of momentum and sensible heat. To examine the performance of these two methods, direct eddy correlation measurements were carried out above a nonuniform grass-covered forest clearing in...

It is argued that in heavy ion collisions at LHC there could be a sizeable production of baryons containing two or three heavy quarks from statistical coalescence. This production mechanism is peculiar of Quark Gluon Plasma and the predicted rates, in heavy ion collisions at LHC energy, should exceed those from a purely hadronic scenario, particularly for Ξbc and Ωccc. Thus, besides the interes...

Reynolds-averaged Navier–Stokes (RANS) methods often cannot predict shock/turbulence interaction correctly. This may be because RANS models do not account for the unsteady motion of the shock wave that is inherent in these interactions. Previous work proposed a shock-unsteadiness correction that significantly improves prediction of turbulent kinetic energy amplification across a normal shock in...