Limitations of the effective field approximation for fluid modeling of high frequency discharges in atmospheric pressure air: Application in resonant structures
Abstract
We study analytically and demonstrate numerically that the local effective field approximation (LEFA) for plasma fluid modeling of high-frequency (GHz-THz) discharges in atmospheric pressure air is not valid in regions where the time scale for electron energy transfer to heavy particles is less than the time-period of the electromagnetic (EM) wave. Greater than 50% modulation of the electron temperature around its mean value is found for frequencies around and under 10 GHz for atmospheric pressure air discharges. This modulation decreases significantly as the EM wave frequency increases. Fully coupled numerical simulation of a resonant metallic cut-array illuminated by high frequency EM waves demonstrates that the LEFA can lead to significant errors on both temporal and spatial evolution of the plasma, in cases where this modulation is significant. The LEFA for high pressure air discharges is found to be valid when the EM wave frequency is around or higher than 100 GHz. For lower frequencies or when the reduced electric fields are high enough, the Local Energy Approximation should be used for an accurate description of the plasma development. For low gas pressures, the modulation is very low rendering the LEFA valid over a large EM wave frequency range.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2017
- Source ID
- 10.1063/1.5004560
Entities
People
- Konstantinos Kourtzanidis
- Laxminarayan L. Raja
Organizations
- Air Force Office of Scientific Research
- University of Texas at Austin