Date of Award

Fall 2021

Document Type

Open Access Thesis


Mechanical Engineering

First Advisor

Sang Hee Won


Quantitative structure property relationship (QSPR) regression models were developed based on the chemical functional group distribution of toluene reference fuels (TRF, mixtures of n-heptane, iso-octane, and toluene) for RON, MON, and DCN. The QSPR regression models were developed using DCN measurements from this study as well as RON/MON data available in literature. The correlations between RON/MON and DCN were analyzed. The ignition propensity of TRFs perturbed by NO addition was also investigated in this study. The interactions between the chemical functional groups and NO were investigated using an ignition quality tester (IQT). It was found that the increase in the ignition propensity of TRFs after NO perturbation was directly related to the mole fraction of the (CH2)n chemical functional group present in the TRFs. The chemical functional group distributions of an ethanol free gasoline with an AKI of 89 and five distillation cuts of the gasoline were determined using Nuclear magnetic resonance (NMR). The NMR analysis suggests that the mole fraction of the (CH2)n functional group decreases from the lighter end of the distillation cuts to the heavier end of the distillation cuts. The current research suggests that the autoignition associated with knock and low speed pre-ignition (LSPI) in internal combustion engines may be caused by the interactions between NO, either left in the cylinder from the previous cycle or introduced by exhaust gas recirculation, and the (CH2)n functional group in gasoline.