Context. The major challenges for a fully polarized radiative transfer driven approach to Zeeman-Doppler imaging are still the enormous computational requirements. In every cycle of the iterative interplay between the forward process (spectral synthesis) and the inverse process (derivative based optimization) the Stokes profile synthesis requires several thousand evaluations of the polarized ra...

Herein, we report on the synthesis and characterization of novel fluorescent fatty acids with large Stokes shifts. Three examples consisting of the same number of carbon atoms and thus of similar chain length are presented differing in their degree of unsaturation. As major fluorogenic contributor at the terminus benzo[c][1,2,5]thiadiazole was used. Respective syntheses based on Wittig reaction...

– We prove some asymptotic results concerning global (weak) solutions of compressible isentropic Navier–Stokes equations. More precisely, we establish the convergence towards solutions of incompressible Euler equations, as the density becomes constant, the Mach number goes to 0 and the Reynolds number goes to infinity.  2001 Éditions scientifiques et médicales Elsevier SAS RÉSUMÉ. – Nous prouv...

We calculate the force on a periodic array of spheres in a viscous ow at small Reynolds number and for small volume fraction. This generalizes the known results for the force on a periodic array due to Stokes ow (zero Reynolds number) and the Oseen correction to the Stokes formula for the force on a single sphere (zero volume fraction). We use a generalization of Hasimoto's approach that is bas...

Consider a Newtonian fluid of kinematic viscosity ν and density ρ confined in a finite cylinder of radius R and height H, whose sidewall oscillates harmonically in the axial direction, with period T and maximum axial velocity Vmax, while the top and bottom lids remain at rest. There are three non-dimensional parameters in this problem: the aspect ratio, Γ = H/R, the Reynolds number, Re = VmaxR/...

We demonstrate that the requirement of Galilean invariance determines the choice of H function for a wide class of entropic lattice-Boltzmann models for the incompressible Navier-Stokes equations. The required H function has the form of the Burg entropy for D=2, and of a Tsallis entropy with q=1-(2/D) for D>2, where D is the number of spatial dimensions. We use this observation to construct a f...

(Received ?? and in revised form ??) We calculate the force on a periodic array of spheres in a viscous ow at small Reynolds number and for small volume fraction. This generalizes the known results for the force on a periodic array due to Stokes ow (zero Reynolds number) and the Oseen correction to the Stokes formula for the force on a single sphere (zero volume fraction). We use a generalizati...

We report experimental evidence of spatial clustering of dense particles in homogenous, isotropic turbulence at high Reynolds numbers. The dissipation-scale clustering becomes stronger as the Stokes number increases and is found to exhibit similarity with respect to the droplet Stokes number over a range of experimental conditions (particle diameter and turbulent energy dissipation rate). These...

An error minimization method is presented for Stokes polarimeters applicable when the detected signals are affected by a combination of shot and Gaussian noise. The expectation of the Stokes vector variance is used as a performance measure. This measure is compared with the condition number of a polarization state analyzer matrix that is commonly used as a figure of merit. We show that a polari...

0017-9310/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.ijheatmasstransfer.2009.07.017 * Corresponding author. Address: Centro Atómico 8400, Rio Negro, Argentina. E-mail address: [email protected] (F.E. Terue A large set of microscopic flow simulations in the Representative Elementary Volume (REV) of a porous medium formed by staggered square cylinders is presented. For each Reynol...