Liquid Precursor Plasma Spraying: Modeling the Interactions Between the Transient Plasma Jet and the Droplets

Abstract

International audiencePlasma spraying using liquid feedstock makes it possible to produce thin coatings (<100 lm) with more refined microstructures than in conventional plasma spraying. However, the low density of the feedstock droplets makes them very sensitive to the instantaneous characteristics of the fluctuating plasma jet at the location where they are injected. In this study, the interactions between the fluctuating plasma jet and droplets are explored by using numerical simulations. The computations are based on a three-dimensional and time-dependent model of the plasma jet that couples the dynamic behaviour of the arc inside the torch and the plasma jet issuing from the plasma torch. The turbulence that develops in the jet flow issuing in air is modeled by a large Eddy simulation model that computes the largest structures of the flow which carry most of the energy and momentum

A Comprehensive Review on Fluid Dynamics and Transport of Suspension/Liquid Droplets and Particles in High-Velocity Oxygen-Fuel (HVOF) Thermal Spray

“…The large eddy simulation (LES) approach has been recently used to simulate thermal sprays, especially atmospheric plasma spraying processes [51][52][53][54]. The LES approach is based on spatially filtering the instantaneous equations [21].…”

Influence of Plasma Intensity on Wear and Erosion Resistance of Conventional and Nanometric WC-Co Coatings Deposited by APS

“…Marchand et al [57] han demostrado para un tamaño de partículas dado que una gran frecuencia de fluctuaciones en la tensión del arco y una fluctuación de esa misma tensión de baja amplitud de conducen a una dispersión del chorro de plasma más débil y un tratamiento térmico más homogéneo. Las fluctuaciones implican que cada partícula tiene su propio historial térmico que depende del instante de penetración en el plasma y de su trayectoria en la periferia o en el corazón del plasma [53].…”

Investigation of Droplet Atomization and Evaporation in Solution Precursor Plasma Spray Coating

“…The influence of the injection angle, the position of the injected plasma jet, and the interactions between the transient plasma flow and feedstock, droplets, or particles have been considered in many simulation works [11][12][13]. However, particle behavior in SPPS, especially during atomization and evaporation, are still under deep exploration.…”