Term of Award

Fall 2022

Degree Name

Master of Science, Mechanical Engineering

Document Type and Release Option

Thesis (open access)

Copyright Statement / License for Reuse

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.


Department of Mechanical Engineering

Committee Chair

Valentin Soloiu

Committee Member 1

Marcel Ilie

Committee Member 2

Mosfequr Rahman


A study was conducted to investigate the low temperature combustion (LTC) regions of aerospace F24 and ULSD in the static setting of a CVCC and the dynamic setting of a CRDI research engine. This research is conducted to reduce in-cylinder emissions by understanding and implementing a technique to achieve an extended LTC. Emissions data for this study were collected during the operation of the CRDI research engine with a MKS 2030 FTIR and an AVL Microsoot 483. The parameters researched within the static setting of the CVCC included the determinations of the cool flames and NTC regions within the LTHR region. Investigations using the CRDI research engine included eight trials. These trials consisted of a baseline for each directly injected fuel, a trial with 0.24 bar of boosted intake air, a trial with 20% of recirculated exhaust gas, and finally a trial with PFI injections of a low reactivity bio-alcohol, n-butanol, during the intake stroke to cool the combustion chamber. PFI parameters also include additions of 0.24 bar of boost, 10% recirculated exhaust gas, and a pilot direct injection 60° BTDC. The low reactivity PFI fuel is utilized to facilitate an extended LTC. The CVCC results concluded with F24 and ULSD obtaining equal values for peak pressure and peak temperature, with the values of 42.3 bar and 1837.5 K, respectively. F24 maintained a longer period of cool flame formations and overall LTHR with values of 1.6ms and 1.96ms, respectively. The mass fraction burned results of ULSD within both the CVCC and dynamic setting of the CRDI research engine yielded better efficiency than F24 in nearly all trials. The trials implementing a LTC method within the CRDI research engine, was found to extend the low temperature combustion region of both F24 and ULSD. PFI trials reduced ignition delay by approx. 3 CAD and massively reduced soot emissions of ULSD and F24 by 9.9 and 2.5 times, respectively, compared to ULSD at baseline parameters. This reduction of soot was the greatest in-cylinder emissions reduction in the entire study. ULSD performed better overall in gaseous emissions outputs.

OCLC Number


Research Data and Supplementary Material