Abstract
This model describes the production and destruction mechanism of nitrogen plasma at atmospheric pressure. We have studied the mechanisms of chemical dissociation, ionization, ion conversion and recombination in nitrogen plasmas, with kinetic temperature (<i>T<sub>g</sub></i>) of the free electrons being higher than the kinetic temperature (<i>T<sub>g</sub></i>) of heavy species. Therefore, the investigation of nitrogen plasma species in a wide range of pressure from 1 Torr to 760 Torr is interesting phenomena for obtaining the equilibrium state when the nitrogen species breakdown. In order to calculate the species densities to reach thermodynamic equilibrium under various conditions, a set of chemical kinetic reactions of nitrogen under consideration have been simulated. It solves the particle balance equations for a set of interacting species. In this study 16 reactions and 4 species of Nitrogen <i>N, N<sub>2</sub>, N<sup>+</sup>, N<sub>2</sub><sup>+</sup></i> and electron have been considered. The densities of the charged and neutral species are modeled by continuity equations which includes the relevant plasma-chemical kinetics. Nitrogen species density is guided by continuity equation where chemical processes and Arrhenius form are used to follow the change of species density over the time. To calculate the species densities over pressure, temperature and time the continuity equations of the 16 reactions for the 5 species under consideration giving their initial pressure, densities and temperatures, with the latter held constant have been solved. The variations of species densities have been investigated as a function of pressure ranging from 1 to 760 Torr. This model shows that as the pressure is increased the species densities of nitrogen plasma also increase from pressure 1 to 200 Torr and after pressure above 200 Torr the species densities become almost saturated. The change of species densities at various temperatures ranging from 2000 Kelvin to 25000 Kelvin is successfully investigated. The destruction and production rates of the nitrogen species also have been calculated within the time ranging from 0 to 19nS and it shows that the density of nitrogen plasma increases with time. In our study we have considered the gas and electron temperature as 10k Kelvin and 4eV respectively.
Highlights
When two particles collide, various phenomena may occur [1]
The Boltzmann equation can provide much more information than the continuum fluid model, its solution is computationally intensive requiring an order of magnitude more computer time than the fluid calculation as kinetic model are inherently higher dimensional and the solutions are functions of the velocity, space and time, the additional degrees of freedom being described in the full phase space of the problem
Kinetic model has developed to simulate the transient behavior on the plasma composition properties of nitrogen plasma at atmospheric pressure
Summary
Various phenomena may occur [1]. One or both particles may change their momentum or their energy, neutral particles can become ionized, and ionized particles can become neutral. For electrons colliding with atoms, the main processes are elastic scattering in which primarily the electron momentum is changed, and inelastic processes such as excitation and ionization. For ions colliding with atoms, the main processes are elastic scattering in which momentum and energy are exchanged, and resonant charge transfer. Other important processes occur in molecular gases. These include dissociation, dissociative recombination, processes involving negative ions, such as attachment, detachment, and positive–negative ion charge transfer, and processes involving excitation of molecular vibrations and rotations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
