Investigation of a side wall heated cavity by using lattice Boltzmann method

International audienceThe lattice Boltzmann method based on the BGK model has been used to simulate laminar natural convection in a heated rectangular cavity on the uniform grid. The hydrodynamic and thermal fields are solved by using the double populations approach. A general benchmark has been carried out to show the effects of secondary parameters at their wide range. Excellent agreement is obtained by comparison with available literatur

Lattice Boltzmann Computation of Plasma Jet Behaviors: part II Argon-Nitrogen Mixture

Abstract – In this paper an innovative computational approach, namely the Lattice Boltzmann Method (LBM), is used for simulating and modeling plasma jet behaviors. Plasma jets are a high temperature flows, then all physical parameters are temperature dependent. This work aims to address the issue of simulating plasma-jet from the point of view of extending the applications to simulating flows with temperature-dependent diffusion parameters (viscosity and diffusivity), focusing on the phenomena occurring in plasma-jet flow for a mixture of plasma gases, N2-Ar62.5 % vol. Argon and Nitrogen are two gases of the most ones used in plasma spraying. The mixture is used when looking for some jet properties. We limit our effort to take out the dynamic and thermal characteristics of this complex flow using the lattice Boltzmann equation. An important section focuses mainly on the validation of our results with compute jet dynamics software such as GENMIX and Jets&Poudres developed in laboratory SPCTS in several updated edition. These codes established for many turbulence models (k-epsilon, k-omega, Prandtl's models…) are helpful numerical keys for understanding the physics of plasma jets and plasma spraying. Our numerical results based on the centerline temperature and velocity profiles, its distributions over the computational domain, the gaussian radial profiles and the effects of inlet quantities are analyzed. The quality of the results shows a great efficiency for the lattice Boltzmann method

A model for rapid solidification for plasma spraying

International audienceA two-dimensional heat transfer model, extended phase change, is developed with an enthalpy formulation in order to predict the splat/substrate thermal story and its effects on plasma surface interaction. The model validated with respect to experimental results is used to estimate the early solidification of yttria stabilized zirconia splat deposited on a cooled substrate. Simulations quantify transfers in terms of some working parameters such that the splat thickness, the splat/substrate contact quality, the latent heat of solidification and the initial temperature

Some benchmarks of a side wall heated cavity using lattice Boltzmann approach

International audienceThe simplified thermal lattice Boltzmann model (STLBM) developed by Peng, Shu and Chew (2003) is used in this work to simulate low-Rayleighnumber natural convection in a heated rectangular cavity on a uniform grid. It is shown how by resorting to the double populations approach both hydrodynamic and thermal fields can be effectively simulated. Furthermore, a general benchmark is carried out to account for the effect of different parameters in relatively wide ranges. Results are compared with previous works available in the literature

Rapid solidification study of stabilized zirconia under plasma spraying

International audienceThis paper presents a numerical study of transient heat transfer and phase change of a thermal spray coating problem. The early solidification of yttria stabilized zirconia splat deposited on a cooled substrate is considered. These phenomena are quantified in terms of some working parameters such that: the splat thickness, the splat/substrate contact quality, the latent heat of solidification and the initial temperatures. A two-dimensional heat transfer model, extended phase change, is developed with an enthalpy formulation in order to predict the splat/substrate thermal story and its effects on plasma surface interaction. The results are in good agreement with an experimental one for the case of a nickel splatting on an alumina substrate