SUMMARY We consider a Leray model with a deconvolution-based indicator function for the simulation of incompressible fluid flow at moderately large Reynolds number (in the range of few thousand) with under-resolved meshes. For the implementation of the model, we adopt a three-step algorithm called evolve-filter-relax (EFR) that requires (i) the solution of a Navier-Stokes problem, (ii) the solu...

In the past decade a large amount of analysis techniques have been scaled down to the microfluidic level. However, in many cases the necessary sample preparation, such as separation, mixing and concentration, remains to be performed off-chip. This represents a major hurdle for the introduction of miniaturized sample-in/answer-out systems, preventing the exploitation of microfluidic’s potential ...

SUMMARY We consider a Leray model with a deconvolution-based indicator function for the simulation of incompressible fluid flow at moderately large Reynolds number (in the range of few thousand) with under-resolved meshes. For the implementation of the model, we adopt a three-step algorithm called evolve-filter-relax (EFR) that requires (i) the solution of a Navier-Stokes problem, (ii) the solu...

The propagation of small perturbations in complex geometries can involve hydrodynamic-acoustic interactions, coupling acoustic waves and vortical modes. A propagation model, based on the linearized Navier–Stokes equations, is proposed. It includes the mechanism responsible for the generation of vorticity associated with the hydrodynamic modes. The linearized Navier–Stokes equations are discreti...

The interactive processes of shallow water flow, sediment transport, and morphological evolution constitute a hierarchy multi-physical problems significant interests in spectrum engineering science areas. To date, modelling hydro-sediment-morphodynamic (SHSM) is subject to multiple sources uncertainty arising from input data incomplete understanding the underlying physics. A stochastic SHSM mod...

We introduce a general characterization of sudden cosmological singularities and investigate the classical stability of homogeneous and isotropic cosmological solutions of all curvatures containing these singularities to small scalar, vector, and tensor perturbations using gauge invariant perturbation theory. We establish that sudden singularities at which the scale factor, expansion rate, and ...

Taylor series expansions of turbulent time correlation functions are applied to show that helicity influences Eulerian time correlations more strongly than Lagrangian time correlations: to second order in time, the hclicity effect on Lagrangian time correlations vanishes, but the helicity cffect on Eulerian time correlations is nonzero. Fourier analysis shows that the hclicity effect on Euleria...

This paper estimates international spillover e§ects of US Quantitative Easing (QE) on emerging market economies. Using a Bayesian VAR on monthly US macroeconomic and financial data, we first identify the US QE shock with non-recursive identifying restrictions. This identified shock is then used in another Bayesian panel VAR for emerging market economies to infer the international spillover e§ec...

The aim of this paper is to characterize two-phase phenomena occurring for a rapid energy discharge in the fluid leading explosive vapour expansion. This study was motivated by lack macro-scale experiments characterizing those transient at high reduced pressure. For that purpose, complete test section designed based on Joule effect deliver discharge. CO2 chosen as working fluid, allowing work s...

BACKGROUND Research into the causes of small-vessel stroke has been hindered by technical constraints. Cases of intracerebral hemorrhage occurring in unusual clinical contexts suggest a causal role for sudden increases in blood pressure and/or cerebral blood flow. CASE DESCRIPTION We describe a fatal primary thalamic/brain stem hemorrhage occurring in the context of sudden emotional upset. At...