This project is focused on developing advanced combustion strategies for mixing-controlled compressionignition (i.e., diesel-cycle) engines that are synergistic with renewable and/or unconventional fuels in a manner that enhances domestic energy security, economic competitiveness, and environmental quality. During this reporting period, the focus was on ducted fuel injection (DFI), a technology that differs from conventional diesel combustion (CDC) in that it involves injecting fuel along the axis of one or more small cylindrical ducts within the combustion chamber. Each duct performs a function similar to the tube on a Bunsen burner, helping to premix the fuel with the charge-gas before ignition, creating a stable flame that forms little to no soot. The purpose of the work conducted during Fiscal Year (FY) 2019 was to begin determining the extent to which the use of oxygenated fuels, when combined with DFI and charge-gas dilution, can simultaneously lower the soot and nitrogen-oxides (N0<
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