Characterization of thermo-chemical properties of electric arc plasma actuators

The potential of plasma actuators for high-speed flow control has motivated significant recent research, particularly focusing on the physics and applications of localized arc filament plasma actuators (LAFPAs) and pulsed plasma jets. In an effort to better understand the physics behind the effect that results in the flow actuation of these devices, the thermal properties of the plasma in a LAFPA were investigated by employing high-resolution, time-resolved and low- and intermediate-resolution, spatially-resolved spectroscopy. The high-resolution, time-resolved experiments yielded a temperature history over the duration of a plasma pulse. The rotational and vibrational temperatures of the N2 in the plasma were seen to rise significantly as the pulse progressed despite the most intense emission occurring at the early times in the pulse. The low-resolution, spatially-resolved experiments characterized the behavior of four key excited species in the plasma during a pulse: atomic tungsten (W), NO, N2, and OH. Significant spatial variation and evolving spectral features were demonstrated within the first microsecond of the pulse except at very high frequencies. The intermediate-resolution experiments confirmed the temporal trends yielded by the high-resolution experiments with the rotational and vibrational temperatures rising significantly and abruptly after the early times in a pulse. It was therefore demonstrated that temporal and spatial variations in the plasma must be taken into account to fully characterize the thermal behavior of these actuators. Finally, to begin to characterize the effect of these plasmas on a supersonic flow and boundary layer, a pulsed plasma jet was injected into a Mach 3 cross-flow, and schlieren imaging experiments were conducted, indicating the formation of a weak bow shock propagating into the flow. A disturbance in the boundary layer was observed in these images.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2012

Author dc:creator

• Sanders, Bradley

Contributors dc:contributor

• Glumac, Nick G.
• Elliott, Gregory S.

• SparkJet
• Plasma actuators
• Plasma actuators for supersonic flow control
• Localized arc filament plasma actuator (LAFPA)
• Pulsed plasma jet
• High-speed flow control
• Supersonic flow control
• Mach 3 cross-flow thermal properties
• Spectroscopic measurements
• Spectroscopy
• Plasma temperature
• Joule heating
• Joule heating effect
• Time-resolved spectroscopy
• Spatially-resolved spectroscopy
• Schlieren imaging
• Mach 3 boundary layer disturbance
• Plasma temperature time dependence
• Temporal Dependence of thermal properties
• Nitrogen second positive system
• High-resolution plasma spectroscopy
• N2 second positive system
• Plasma rotational temperatures
• LAFPA rotational temperatures
• LAFPA vibrational temperatures
• Plasma vibrational temperatures
• LAFPA rotational temperature
• Plasma rotational temperature
• LAFPA vibrational temperature
• Plasma vibrational temperature
• Pulsed plasma jet injection
• Plasma-induced bow shock
• Pulsed plasma jet injection in a mac 3 cross-flow
• Electric arc plasma actuators
• Mach 3 boundary layer plasma actuation
• Mach 3 cross-flow plasma actuation
• High-speed flow plasma actuation

Statement dc:rights

• Copyright 2012 Bradley Sanders

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/31165

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F31165