Publication Date

2008

Document Type

Thesis

Committee Members

James Menart (Committee Chair), Scott Thomas (Committee Member), J. Mitch Wolff (Committee Member)

Degree Name

Master of Science in Engineering (MSEgr)

Abstract

Investigations into two different fields of plasma research are presented here. These include the study of ion engine performance and the use of plasma discharges for flow control. In the area of ion engine performance, optimizing electron confinement is the primary goal of this work. The work of prior researchers was expanded through the study of the cathode emission location and the energy of the primary electrons. Cathode position was shown to have minimal effect on confinement length. For electron energy values greater than 20eV the effect on confinement length was also found to be very small. The strength of the magnetic field was also tested and compared with results from prior researchers. The results showed that for a magnet circuit that is already optimized, increasing the magnetic field strength through adding more magnets or using stronger magnets only decreases the confinement. In the area of plasma actuators for flow control, the objective is to garner a qualitative understanding of both heating and the addition of forces to subsonic and hypersonic flows. This was done through the use of a commercially available CFD package. Results showed that for plasma discharges the dominant effect on surface pressure in the hypersonic regime is that of heating. Representative force sources showed some effect but were smaller. Subsonic computational studies showed that heating had no significant effect on the pressure distribution. Results for the force sources show that it is possible to get some small changes in the surface pressure through the use of a sufficiently large force. Experimental results conducted in a subsonic wind tunnel confirmed the minimal influence of the heating effect. Long range Lorentz forces were obtained by placing magnets within the plate. The resulting forces on the plate match well with the Lorentz force law, but due to limitations in power, the plasma discharge did not reach the desired length.

Page Count

134

Department or Program

Department of Mechanical and Materials Engineering

Year Degree Awarded

2008

Download


Share

COinS