atmospheric pressure

Unified modelling of low-current short-length arcs between copper electrodes

In this work we present for the first time a unified model of a low-current short-length arc between copper electrodes. The model employs one-dimensional fluid description of the plasma in argon and copper vapour at atmospheric pressure and the heat transfer in the electrodes made of copper. The solution of the particle and energy conservation of electrons and heavy particles is coupled with the solution of the Poisson equation, from which the self-consistent electric field is obtained. The operation of the non-refractory cathode is based on thermo-field emission.

Plasma parameters of microarcs towards minuscule discharge gap - Dataset

This dataset contains plasma parameters of microarcs generated between a cooled copper anode and a ceriated tungsten cathode by means of a one-dimensional unified non-equilibrium model for gap lengths between 15 and 200 µm and current densities from 2x10^5 up to 10^6 A/m^2. The data show that the decrease of the gap length down to a few tens of micrometers for a given current density results in a progressive shrinking of the quasineutral bulk in the microplasma and its complete disappearance.

Study of the anode energy in gas metal arc welding

Recent research of gas metal arc welding (GMAW) has proven that the sheath voltage dominates the total voltage fall in the current circuit and delivers most of the energy, which is finally transferred to the wire and the weld pool. This data set provides the results for droplet temperatures and the energy delivered to the wire anode in comparison with the sheath voltages. These quantities have been studied experimentally for a typical pulsed GMAW process in the one drop per pulse mode for mild steel under Ar with 2.5% CO2 with different peak currents from 350 to 650 A.

A simplified voltage model in GMAW

The relation between the voltage and the arc length in gas metal arc welding (GMAW) is an important characteristic. It depends on a complex distribution of the electric conductivity along the current path and does not depend on the arc length only. Based on electric measurements and the arc length determination from high-speed arc images, a simplified electrical model is introduced for a pulsed GMAW process. It shows the relation of voltage, current, arc length and free wire length and considers also their temporal evolution during the process in particular during the high-current phase.

Comparison of six simulation codes for positive streamers in air

The dataset includes all the input and output files for the paper: Comparison of six simulation codes for positive streamers in air (https://doi.org/10.1088/1361-6595/aad768). Three test cases for axisymmetric positive streamers are described in the paper. The codes are of the finite volume or the finite element type, and they use both explicit and implicit time stepping. The computational domain and initial conditions are kept simple, so other codes can be compared relatively easily to the data published here.

Plasma parameters in an Ar-HMDSO DBD at atmospheric pressure for plasma-polymerization experiments

The plasma parameters of a large-area dielectric barrier discharge (DBD) in argon-HMDSO mixtures containing up to about 1600 ppm of the monomer are investigated by means of numerical modelling. A time-dependent,
spatially one-dimensional fluid model is applied, taking into account the spatial variation of the discharge plasma between plane-parallel dielectrics covering the electrodes. The dataset contains values of power dissipated in the DBD as well as the space- and period-averaged density and mean energy of the electrons as a function of HMDSO admixture.

High-speed thermal microscopy of plasma microprinting at atmospheric pressure

The HelixJet (https://www.inptdat.de/helixjet) was applied to simultaneous melting and plasma treatment of polyamide (PA 12) microparticles (diameter 60 µm) used conventionally for 3D printing by laser sintering. This proof-of-principle experiment demonstrated that gaussian thickness profiles of PA 12 can be printed using the HelixJet with a rapid rate of 200 mg/s (peak growth 2 mm/s) and with advantageous material properties. The key element of this novel process is the self-regulated balance between material melting and plasma quenching.

Correlation of helicality and rotation frequency of filaments in the ntAPPJ

The self-organized behaviour (locked mode) of filaments in the non-thermal atmospheric pressure plasma jet (ntAPPJ) couples a spatial patterning of the discharge (helical symmetry) and a regular motion (steady rotation). The dataset represents the mean rotation frequency of filaments in the capillary with a diameter of 4 mm and the corresponding geometric characteristics: helicality and/or filament inclination angles were measured along with the gas temperature under varying discharge conditions (electric power and argon flow rate).