Scaled-Up Nonequilibrium Air Plasmas
Abstract
This report results from a contract tasking Comenius University as follows: In the first stage of the project we will design a new discharge chamber allowing investigations of the proposed DC discharges in atmospheric pressure steady-state or fast flow conditions, and in lowered pressure. Fast flow conditions will be provided by a special nozzle. The chamber will be optionally mounted on the existing 3 kW microwave plasma torch to investigate discharges in preheated gas flows. The discharge chamber will enable the electrical, optical and spectroscopic diagnostics of the discharges. The measured discharge parameters will allow us to calculate and estimate further properties of the generated non-thermal plasmas. The high voltage generators and the electrical circuits for sustaining optimal discharge regimes have already been constructed. The main stage of the project will be dedicated to the investigations of the discharge properties in various flow, pressure (1 to 0.1 atm) and temperature (ambient vs. preheated to 2000 K) conditions. The two principal objectives will be sought: volume scaling-up and power budget reduction. Both DC glow and pulsed transient spark discharges will be investigated. Various electrode arrangements with several electrode pairs will be tested to increase the plasma volume. In addition, thermionic cathodes (LaCrO3, LaB6) will be examined to enhance the electron number density in the plasma - a key parameter for plasma shielding. In reducing the power budget we will focus on (1) shortening the transient spark pulses that will reduce the energy losses for gas heating, and (2) increasing the pulse repetitive frequency to keep the electron density large enough (greater than 10e12 cm-3) during the relaxation phase between the consecutive pulses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2009
- Accession Number
- ADA521300
Entities
People
- Karol Hensel
- Zdenko Machala
Organizations
- Comenius University