Kinetics of Non-Equilibrium Fast Ionization Wave Plasmas in Gas Phase and Gas-Liquid Interface

Ohio State University, The, Columbus OH

Investigators

Abstract

Nonequilibrium plasma chemistry has been extensively studied recently due to its importance for a variety of engineering applications such as fuel reforming, hazardous emissions reduction,plasma assisted combustion, and plasma flow control. The use of nonequilibrium plasmas for these applications requires both understanding of fundamental kinetic processes involved, and the ability to generate, control, and characterize these plasmas at high pressures, high energy loadings, and in large volumes (over large surface areas). A promising method of generating large-volume, diffuse nonequilibrium plasmas in a wide range of pressures is what is known as the Fast Ionization Wave (FIW) discharge. In this approach, high peak voltage (approximately 10-100 kiloVolt),approximately 10-100 nanosecond duration voltage pulses are used to generate an ionization wave (wave speed of a few cm/nsec) propagating over large distances, up to several tens of centimeters. High electron energy achieved in the wave front dramatically accelerates key plasma processes such as molecular dissociation, thus generating reactive radical species. The project focuses on a comprehensive and fundamental experimental study of the physics and chemistry of FIW plasmas, featuring incorporation of a comprehensive suite of laser-baseed optical diagnostic techniques. In addition its technical goals, the program will also reflect many of the stated NSF criteria for broader impact. In particular, the program will advance "discovery and understanding" by i), direct involvement of graduate and undergraduate students, and ii), incorporation of the diagnostic methods, modeling tools, and principal findings into the undergraduate and graduate Mechanical Engineering curriculum at OSU. Every effort will also be made to broaden the participation in the research program of individuals from groups traditionally underrepresented in mechanical engineering and chemistry. The continued development FIW technology will also serve to enhance the high pressure plasma infrastructure of the U.S (and the world), potentially enabling a wide variety of applications such as: ignition and flame-holding in next generation high speed jet aircraft; high power gas dynamic lasers; and plasma aerodynamic flow control. The co-PIs are actively engaged in the transfer of plasma and advanced optical diagnostic technology as it is continually developed, to the government and industrial sectors through collaborations with the U.S Air Force, NASA, and a variety of small businesses. Finally, by maintaining an active web site, and by student and PI participation in national and international meetings, the principal findings will be rapidly disseminated to the scientific and educational communities at large.