Global Modeling of N₂O Discharges: Rate Coefficients and Comparison with ICP and Glow Discharges Results

Abstract

We developed a Global Model for N2O plasmas valid for applications in various power, gas flow rate, and pressure regimes. Besides energy losses from electron collisions with N2O, it takes into consideration those due to molecular N2and O2and to atomic N and O species. Positive atomic N+and O+and molecular N2O+,N2+, andO2+have been treated as separate species and also negative O−ions. The latter confer an electronegative character to the discharge, calling for modified plasma sheath and plasma potential formulas. Electron density and temperature and all species densities have been evaluated, hence the ionization and dissociation percentages of N2O, N2, and O2molecules and the plasma electronegativity. The model is extended to deal with N2/O2mixtures feedings, notably with air. Rate coefficients and model results are discussed and compared with those from available theoretical and experimental work on ICP and glow discharge devices.

Global Modeling of N2O Discharges: Helicon Plasma Thruster Application

“…It is defined as the sum of the ions densities over the total density of species. The and variations shown in Figure 3 are somewhat analogous with those observed for both the N 2 O and the Ar PR cases (see [1,2]), even if variations are more intense for the thruster and encompass a wider range of values.…”

“…General description and characteristics of the used GM for N 2 O and for N 2 /O 2 mixtures feedings follow those of [1] and are not repeated here. However, we note that the simplification of the collisional energy loss for species , , = 2 pertaining to the collisionless Landau damping mechanism in relatively low pressure plasmas heated by 2 International Journal of Aerospace Engineering helicon waves which is proposed in [4] was used for the energy losses in the "core" region of the HPT.…”

Global Modeling of CO2 Discharges with Aerospace Applications

“…Processes involving carbon species are contained in Table 4. Table 3 constitutes an extended version of Table 4 appearing in [12]. No source is given for cross sections/rate coefficients for which references are available in [12].…”

“…Table 3 constitutes an extended version of Table 4 appearing in [12]. No source is given for cross sections/rate coefficients for which references are available in [12]. Moreover, reference [17] contains an extended list of related references.…”

“…Description of the GM elaboration techniques is not reported here, as it is available elsewhere (see e.g., [1,2,11] and references therein). Also, sensitivity of the used parameters is not specifically investigated, because previous GM studies of various plasmas compositions showed in general a smooth variation [12]. In Section 3, theoretical results obtained from our model and general considerations concerning CO 2 discharges in higher pressures, pertaining to lower electron temperatures ( e ), are given and commented.…”