Atmospheric dispersion is a topic of great importance especially in relation to pollutant transport. Two different approaches, known as the Eulerian and the Lagrangian frameworks, are used to describe this process. In the Eulerian framework, statistical properties are calculated in a fixed reference frame. This approach is most commonly used in field experiments as well as in laboratory experim...

Subcooled flow boiling in multi-microchannels can be used as an efficient thermal management approach in compact electrical devices. Highly subcooled flow boiling of HFE 7100 is studied in two microchannel heat sinks to choose a proper numerical model for simulating boiling flows in microchannels. Results of five different numerical models, including Volume of Fluid (VOF), Eulerian boiling, Eul...

We develop an ELLAM (Eulerian-Lagrangian localized adjoint method) scheme to solve two-dimensional advection-diiusion equations with all combinations of innow and outtow Dirichlet, Neumann, and ux boundary conditions. The ELLAM formalism provides a systematic framework for implementation of general boundary conditions, leading to mass-conservative numerical schemes. The computational advantages...

The issue of the parameterization of small-scale dynamics is addressed in the context of passive-scalar turbulence. The basic idea of our strategy is to identify dynamical equations for the coarse-grained scalar dynamics starting from closed equations for two-point statistical indicators. With the aim of performing a fully-analytical study, the Kraichnan advection model is considered. The white...

is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. f a b s t r a c t We present a simple numerical method to simulate the interaction of two non-miscible compressible materials separated by an interface. The media considered may have significantly different physical properties and constitutive l...

A poset P is called k-Eulerian if every interval of rank k is Eulerian. The class of k-Eulerian posets interpolates between graded posets and Eulerian posets. It is a straightforward observation that a 2k-Eulerian poset is also (2k+1)-Eulerian. We prove that the ab-index of a (2k+1)Eulerian poset can be expressed in terms of c = a + b, d = ab + ba and e2k+1 = (a − b)2k+1. The proof relies upon ...