Foest, Rüdiger

Modelling and experimental evidence of the cathode erosion in a plasma spray torch

The lifetime of tungsten cathodes used in plasma spray torches is limited by processes leading to a loss of cathode material. It was reported in the literature that the mechanism of their erosion is the evaporation. A model of the ionization layer of a cathode is developed to study the diffusive transport of evaporated tungsten atoms and tungsten ions produced due to ionization by electron impact in a background argon plasma.

Effect of a spatially fluctuating heating of particles in a plasma spray process - Dataset

The work is concerned with the effect of a spatially fluctuating heating of Al_2O_3 particles with diameters of 5–120 μm during a plasma spray process. A plasma jet is generated in a mixture of Ar (40 NLPM) and H_2 (14 NLPM) and in pure Ar at an electric current of 600 A. The tracing of the injected particles in the plume region of the plasma jets is considered in the framework of a three-dimensional model taking into account a turbulent fluid flow.

Self-consistent Cathode-Plasma Coupling and Role of the Fluid Flow Approach in Torch Modelling - Dataset

The data set is related to a two-dimensional and stationary magneto-hydrodynamic model of a plasma spray torch operated with argon, which is developed to predict the plasma properties in a steady operating mode. The model couples a submodel of a refractory cathode and its non-equilibrium boundary layer to a submodel of the plasma in local thermodynamic equilibrium in a self-consistent manner. The Navier-Stokes equations for a laminar and compressible flow are solved in terms of low- and high-Mach number numerical approaches.

The effect of oxygen admixture on the properties of microwave generated plasma in Ar-O₂ : a modelling study - dataset

This work presents the datasets of the results of a self-consistent modelling analysis on microwave plasma generated in Ar-O₂ mixtures at a frequency of 2.45 GHz at atmospheric pressure. The study focuses on how the plasma properties are in uenced by the increase of the oxygen fraction in the gas mixture. The oxygen admixture is increased from 1 up to 95 % in mass for values of the input microwave power of 1 and 1.5 kW.

Cold plasma for implement for plasma treatment of surfaces

A plasma tool for generating a cold plasma beam (10) is described. The plasma tool is defined by the fact that it has a plasma nozzle, in particular a plasma nozzle which is dimensioned for operation by hand, wherein at least the coil (6) of the adaptation network is integrated into the plasma nozzle, for operation with a high frequency generator in addition to the capacitor C2, while the capacitor C1 can be arranged in the generator itself or in its vicinity.