Date of Award
Spring 2023
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Mechanical Engineering
First Advisor
Dempsey, Adam B.
Second Advisor
Allen, Casey M.
Third Advisor
Bowman, Anthony J.
Abstract
With the growing societal concern toward vehicle emissions, renewableforms of fuel are garnering increased interest in the fuel research world. While electrification is prevalent amongst the light duty sector, many challenges arise for such type of powerplant in heavy duty vehicles. Further, current heavy duty mixing-controlled combustion uses diesel fuel, which produces significant black carbon emissions in the exhaust. Alcohol fuels from biological sources serve as a promising source ofrenewable energy for heavy duty engines. The soot emissions and thermodynamic properties of ethanol/gasoline blended fuels must be understood and quantified in order to develop heavy duty combustion engine technology capable of ignition with such blends. This work studies the ignition and sooting characteristics of surrogate species for these fuels and real fuel blends during auto-ignition. The results of this work are used in on-going CFD models of the RCM for soot model and chemical kinetic model identification. The experiments are conducted in a rapid compression machine (RCM), a piston cylinder device which uses a homogenous, pre-mixed air fuel charge to study fuel combustion characteristics in a reaction vessel. Sooting tendency is reported as soot volume fraction as a function ofequivalence ratio. Pressure and compressed pressure data are reported for all fuels. To better characterize emissions and fuel combustion, two temperature measurement strategies are applied to the RCM, including a dual thermocouple reconstruction technique and a water vapor absorption spectroscopy methodology. Lastly, single cell adiabatic, constant-volume, CFD simulations are used to glean further information on soot formation of fuel blends and assist in modeling. The results of the studies in this work can be used to improve both CFD simulations and experiments for development of heavy duty engine technology capable of igniting these low-cetane fuel blends.