Session: 04-12: Ignition I

Paper Number: 81134

81134 - Ignition Chemistry of Syngas Highly Diluted in CO2 

Syngas combustion has garnered much interest in the combustion community over the years. Specifically, syngas is a desirable, high-hydrogen fuel source for combustors utilizing the Allam-Fetvedt cycle involving supercritical-CO₂ (sCO₂). While considerable amounts of data exist for syngas combustion, minimal data are available with high concentrations of CO₂, with much of the available data being few in number and reported over very narrow temperature ranges. Additionally, considerable model disagreements have been shown at intermediate pressures (10-100 atm), while good agreement is seen for higher pressures (>100 atm). Additionally, further examination of literature data highlights that the ignition delay time characteristics of syngas at these pressures show little dependence on pressure, mixture composition, and equivalence ratio. To verify these observations, literature experiments were replicated. Some disagreement with literature data is seen, and sources of error from the literature results are discussed. However, similar trends are seen for syngas ignition delay time characteristics. In short, more effort is required to understand the ignition chemistry at these intermediate pressures. To this end, a high-pressure shock tube facility was utilized to collect ignition delay time data for syngas mixtures for pressures between 10 and 70 atm with 85-94% CO₂ mixtures at several equivalence ratios and H₂:CO fuel ratios. Sensitivity analysis using the AramcoMech 2.0 chemical kinetics mechanism highlights important chemical reactions.

Presenting Author: Sean P Cooper Texas A&M University

Presenting Author Biography: Sean P. Cooper graduated in May of 2017, magna cum laude, from the University of New Mexico (UNM) with his Bachelor of Science in Mechanical Engineering. During his time at UNM, he led a team of engineering students in creating the launch pad and launch rail system for UNM’s first rocket program. He also worked with two faculty advisers (Drs. Peter Vorobieff and Randall Truman) and their Ph.D candidates in their shock-tube laboratory. This work eventually became his undergraduate Honor’s Thesis and led him to attend graduate school at Dr. Eric L. Petersen’s combustion lab at the Turbomachinery Laboratory at Texas A&M University. To begin his Ph.D work at Texas A&M, he was awarded the Engineering Graduate Merit Fellowship (EGMF), College of Engineering Fellowship, BakerRisk/Quentin & Jana Baker Fellowship, and the Fowler Fellowship. He has numerous conference and journal publications such as those appearing in the International Colloquium on the Dynamics of Explosions and Reactive Systems (ICDERS) and Fuels. He has since been awarded for outstanding academic achievement and as well as several additional grants and fellowships. Currently he is working on chemical kinetics of gaseous fuels in supercritical CO2 as well as numerous projects on liquid fuel and lubricant ignition.

Authors:

Sean P Cooper Texas A&M University
Darryl J Mohr Texas A&M University
Olivier Mathieu Texas A&M University
Eric L Petersen Texas A&M University