Date: Thursday, September 02, 2021, 02:00 PM - 03:00 PM
Location: Building 3, Level 5, Room #5220
Sustainable and low emission combustion requires new combustion paradigms and solutions to increase efficiency, comply with more stringent regulations on pollutants, and cope with the varying qualities of renewable fuels. Plasma Assisted Combustion (PAC) could be one of the tools to achieve these goals in practical combustion systems. Previous studies showed that PAC could be used in a variety of applications: to improve ignition in challenging environments, to extend the operating range of burners to leaner conditions, to contrast thermoacoustic instability, to allow flame-holding in extreme conditions, and more. While applications keep being proposed, there are efforts to model and understand the coupling between flames and plasma discharges. This work contributes to unraveling the action of plasma discharges on flames by performing several investigations on a simple PAC burner. Trends and temporal evolution of key chemical species and electric fields are measured during plasma actuation of the flame. Experimental datasets resulting from this work are meant to be used in cross-validating numerical simulations. The considered PAC burner generates a lean methane-air stagnation flame, across which discharges are applied, developing partially in a fresh and partially in the burned gases. Time-resolved 2D imaging of atomic hydrogen and oxygen is obtained using two-photon absorption planar laser-induced fluorescence (TALIF), while OH and CH radicals are measured using planar laser-induced fluorescence (PLIF). To measure the electric field, the Electric Field Induced Second-Harmonic generation (EFISH) technique is used. A novel deconvolution-like post-processing procedure is proposed and used to calibrate the measurements and improve the spatial resolution, overcoming the limitations arising from a large interaction volume, typical in EFISH measurements. Presented results quantify the effect of the plasma actuation on the flame and lend themselves to the validation of numerical models.
Davide Del Cont-Bernard obtained his bachelor's in Aerospace Engineering from the Politecnico di Milano, Italy. In the same university he completed his Master's in Aeronautical Engineering focusing on rotary-wing aircraft. In late 2017 he joined KAUST as a Ph.D. student in Mechanical Engineering program in PSE, under the supervision of Prof. Deanna A. Lacoste. His current research interests focus on plasma-assisted combustion and diagnostics.