3D modeling of the plasma co-spraying of two dissimilar materials

International audienceThe co-spraying of a ceramic and a metallic powder for the manufacturing of functionally graded plasma-sprayed coatings is investigated by using a 3D commercial Computational Fluid Dynamics code, ESTET 3.2. The operating conditions of the plasma torch are kept constant and various configurations of the powder injection in the plasma flow are discussed

Divergence-free MHD Simulations with the HERACLES Code

Numerical simulations of the magnetohydrodynamics (MHD) equations have played a significant role in plasma research over the years. The need of obtaining physical and stable solutions to these equations has led to the development of several schemes, all requiring to satisfy and preserve the divergence constraint of the magnetic field numerically. In this paper, we aim to show the importance of maintaining this constraint numerically. We investigate in particular the hyperbolic divergence cleaning technique applied to the ideal MHD equations on a collocated grid and compare it to the constrained transport technique that uses a staggered grid to maintain the property. The methods are implemented in the software HERACLES and several numerical tests are presented, where the robustness and accuracy of the different schemes can be directly compared

Call for contributions to a numerical benchmark problem for 2D columnar solidification of binary alloys

Corrigendum to this publication: http://hal.archives-ouvertes.fr/hal-00528029International audienceThis call describes a numerical comparison exercise for the simulation of ingot solidification of binary metallic alloys. Two main steps are proposed, which may be treated independently: 1. The simulation of the full solidification process. First a specified 'minimal' solidification model is used and the contributors are provided with the corresponding sets of equations. The objective is to verify the agreement of the numerical solutions obtained by different contributors. Then different physical solidification models may be compared to check the features that allow for the best possible prediction of the physical phenomena. 2. A separate preliminary exercise is also proposed to the contributors, only concerned with the convective problem in the absence of solidification, in conditions close to those met in solidification processes. Two problems are considered for the case of laminar natural convection: transient thermal convection for a pure liquid metal with a Prandtl number on the order of 10(-2), and double-diffusive convection in an enclosure for a liquid binary metallic mixture with a Prandtl number on the order of 10(-2) and a Lewis number on the order of 10(4)

Corrigendum to "Call for contributions to a numerical benchmark problem for 2D columnar solidification of binary alloys" [Int. J. Thermal Sci. 48 (11) (2009) 2013-2016]

International audienceRefers to: Call for contributions to a numerical benchmark problem for 2D columnar solidification of binary alloys International Journal of Thermal Sciences, Volume 48, Issue 11, November 2009, Pages 2013-2016, M. Bellet, H. Combeau, Y. Fautrelle, D. Gobin, M. Rady, E. Arquis, O. Budenkova, B. Dussoubs, Y. Duterrail, A. Kumar, C.A. Gandin, B. Goyeau, S. Mosbah, M. Založni

Extended generalized Lagrangian multipliers for magnetohydrodynamics using adaptive multiresolution methods

We present a new adaptive multiresoltion method for the numerical simulation of ideal magnetohydrodynamics. The governing equations, i.e., the compressible Euler equations coupled with the Maxwell equations are discretized using a finite volume scheme on a two-dimensional Cartesian mesh. Adaptivity in space is obtained via Harten’s cell average multiresolution analysis, which allows the reliable introduction of a locally refined mesh while controlling the error. The explicit time discretization uses a compact Runge–Kutta method for local time stepping and an embedded Runge-Kutta scheme for automatic time step control. An extended generalized Lagrangian multiplier approach with the mixed hyperbolic-parabolic correction type is used to control the incompressibility of the magnetic field. Applications to a two-dimensional problem illustrate the properties of the method. Memory savings and numerical divergences of magnetic field are reported and the accuracy of the adaptive computations is assessed by comparing with the available exact solution