Investigation of alternative jet fuels in gas turbine combustion systems using x-ray radiography

The development of alternatives to petroleum-derived jet fuels is essential for assisting in climate change mitigation and providing economic security and energy independence within industries that utilize jet fuels. It is important that jet fuels derived from alternative sources can be used in existing engines with little to no modifications to the engine design or operation. Towards this end, researchers must understand how various fundamental fuel properties affect the atomization, vaporization, and combustion process of jet fuels and ascertain which properties determine if an alternative fuel will behave similarly to conventional jet fuel. In this work, x-ray phase-contrast imaging is performed at 90,517 Hz on a combusting fuel spray in a realistic gas turbine combustor, allowing characterization of breakup process of fuel into ligaments and then individual droplets as it leaves a nozzle. This imaging is performed on two different fuels: Jet-A (A-2), which represents a fuel with standard properties, and C-3 Fuel, which is a blend of JP-5 and farnesane (64% to 36% by volume), which is specifically formulated to be a high-viscosity jet fuel. The fuels are tested over a range of fuel flow rates and inlet air preheat temperatures to establish the effect of various combustor conditions on the atomization and vaporization processes. The phase contrast imaging shows that atomization occurs much more rapidly at higher fuel flow rates and fuel pressures, and that the high viscosity fuel is qualitatively and quantitatively observed to break up into longer ligaments and larger diameter droplets than the standard viscosity fuel. Additionally, increasing the air preheat temperature significantly increases mean droplet velocity and decreases droplet diameters at the same conditions.

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

2019

Author dc:creator

• Wood, Eric James

Contributors dc:contributor

• Lee, Tonghun

• Gas Turbine Combustion
• X-Ray Phase-Contrast Imaging
• Alternative Jet Fuels

Statement dc:rights

• Copyright 2018 by Eric James Wood

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/102857

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/102857