A broad class of engineering problems including penetration, tmpact and large rotations of solid bodies causes severe numerical problems. For these problems, the constitutive equations are history dependent so material points must be followed; this is difficult to implement in a Eulerian scheme. On the other hand, purely Lagrangian methods typically result in severe mesh distortion and the cons...

1 THE FLUID EQUATIONS 2 1.1 Microscopic Description 2 1.2 Macroscopic Description 3 1.3 Velocity Moments and the Fluid Limit 3 2 EULERIAN PERTURBATIVE SOLUTIONS 4 2.1 Linear Density Field 4 2.2 Linear Peculiar Velocity Field 6 2.3 Non-Linear Corrections 7 3 SOME BASIC APPLICATIONS 8 3.1 The PDF as a Measure of Large Scale Structures 8 3.2 Moments of the PDF 9 3.3 Edgeworth Expansion of the PDF ...

Introduction Conclusions References

We analyse acoustic streaming flows using an arbitrary Lagrangian Eulerian (ALE) perspective. The formulation stems from an explicit separation of time scales resulting in two subproblems: a first-order problem, formulated in terms of the fluid displacement at the fast scale, and a second-order problem, formulated in terms of the Lagrangian flow velocity at the slow time scale. Following a rigo...

As a clean and energy-saving natural gas purification separation device, the supersonic separator's internal gas-liquid mechanism needs to be explored. However, complex three-field (gas, droplet, liquid film) two-phase liquid) condensation flow challenges numerical modeling. Most studies are limited tracking phase droplets ignore effects of film change on water vapor removal. In present study, ...

The purpose of this paper is to evaluate the accuracy of the mesoscopic approach proposed by Février et al. [P. Février, O. Simonin, K.D. Squires, Partitioning of particle velocities in gas–solid turbulent flows into a continuous field and a spatially uncorrelated random distribution: theoretical formalism and numerical study, J. Fluid Mech. 533 (2005) 1–46] by comparison against the Lagrangian...

A finite-volume dynamical core with a terrain-following Lagrangian control-volume discretization is described. The vertically Lagrangian discretization reduces the dimensionality of the physical problem from three to two with the resulting dynamical system closely resembling that of the shallow water system. The 2D horizontalto-Lagrangian-surface transport and dynamical processes are then discr...

A hybrid approach to the problem of predicting the dispersion of contaminants (e.g. suspended solids or heated water) in coastal areas is presented. A neutral random walk particle tracking method is adopted in the vicinity of the source point, where steep concentration gradients occur. In the case of heat dispersion particles are assigned with buoyancy, which leads to additive horizontal diffus...

This paper describes a three-dimensional Eulerian-Lagrangian method for the modeling and simulation of high-speed multi-material dynamics. The equations for conservation of mass, momentum, and energy are solved on a fixed Cartesian grid using a fully conservative higher order MUSCL scheme. The dilatational response of each material is handled using a suitable equation of state. The embedded int...

For problems of convection–diffusion type, Eulerian–Lagrangian localized adjoint methods provide a methodology that maintains the accuracy and efficiency of Eulerian–Lagrangian methods, while also conserving mass and systematically treating any type of boundary condition. In groundwater hydrology, this framework is useful for solute transport, as well as vadose-zone transport, multiphase transp...