Ph.D. Thesis Proposal

By

Sheng Wei

(Advisor: Prof. Jerry Seitzman)

9:30 AM, Thursday, March 15, 2018

Montgomery Knight Building Room 317

Forced Ignition of Alternative Jet Fuels in Stratified Flow Field 

ABSTRACT:

Expected worldwide growth in aviation has led to increased interest in exploring alternative, non-petroleum, jet fuel sources. Prior to employing these non-conventional fuels in jet engines, safe and reliable operation needs to be ensured. Besides fuel certification by testing in actual jet engine combustors, studying the important combustion processes in gas turbine combustors in a laboratory setting can provide deeper understanding into fuel composition effects on combustor performance. The study of forced ignition in a stratified flow field with alternative jet fuels is the focus of this doctoral work. Experimental and modeling approaches are employed to gain understanding of the forced ignition process with liquid fuel sprays and of the effect of varying fuel composition on forced ignition. Preliminary experimental results show significant differences in ignition probabilities among the 14 fuels tested. Measurements are performed for prevaporized fuels to isolate fuel chemistry effects, while fuel spray results include the influence of fuel physical properties, e.g., viscosity and volatility. The experimental approach includes high-speed, simultaneous chemiluminescence, OH PLIF, and schlieren imaging. The modeling employs a reduced-order simulation that includes detailed chemistry and entrainment of fuel and air into the plasma kernel created by the ignitor. Results from the reduced order model for the prevaporized fuels can distinguish lean ignition limits for the fuels with available chemical mechanisms. The interplay among droplet atomization, vaporization, and combustion chemistry during an ignition event will be explored using the reduced-order modeling approach coupled with droplet atomization. 

Committee Members: Professor Jerry Seitzman, Professor Jechiel Jagoda, Professor Wenting Sun