The enhanced growth of ignition kernels through modulation of nanosecond pulsed high-frequency discharges is investigated quantitatively in a reactive flow. High-frequency discharge and new notions of rotational temperature coupling per subsequent pulse ( < 30 kHz) existing within the breakdown regime have led to the discovery of the "fully-recoupled" regime. The evolution of flame kernels is observed in a methane-air mixture at an equivalence ratio of 0.6 flowing at 12.5 m/s, with an interelectrode gap of 1.7 mm. Energy deposition into the flow per pulse was previously found to be 2.9 ± 0.23 mJ/pulse, where the number of pulses per effective modulation type was 10 ( ≈ 30mJ). By holding A.P. (average power) constant through each pulse train, the CPRF (Constant Pulse Repetition Frequency) partially-coupled and decoupled regimes were directly compared against the MPRF (Modulated Pulse Repetition Frequency) fully-recoupled regime through kernel growth measurements via high-speed schlieren. It was found that by utilizing the inter-pulse coupling of rotational temperatures through modulating the PRF (Pulse Repetition Frequency), the ignition probability and kernel area increased as to create the fully-recoupled regime as a new form of ignition optimization.
If this is your thesis or dissertation, and want to learn how to access it or for more information about readership statistics, contact us at STARS@ucf.edu
Master of Science in Aerospace Engineering (M.S.A.E.)
College of Engineering and Computer Science
Mechanical and Aerospace Engineering
Aerospace Engineering; Thermofluid Aerodynamic Systems
Length of Campus-only Access
Masters Thesis (Campus-only Access)
Dunn, Ian, "Flame Kernel Ignition and Evolution Induced by Modulated Nanosecond-Pulsed High-Frequency Discharge" (2020). Electronic Theses and Dissertations, 2020-. 207.
Restricted to the UCF community until August 2025; it will then be open access.