This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Ethanol/N-Heptane Dual-Fuel Partially Premixed Combustion Analysis through Formaldehyde PLIF
ISSN: 1946-3936, e-ISSN: 1946-3944
Published April 16, 2012 by SAE International in United States
Citation: Florea, R., Zha, K., Yu, X., Jansons, M. et al., "Ethanol/N-Heptane Dual-Fuel Partially Premixed Combustion Analysis through Formaldehyde PLIF," SAE Int. J. Engines 5(2):483-492, 2012, https://doi.org/10.4271/2012-01-0685.
As a result of recent focus on the control of Low Temperature Combustion (LTC) modes, dual-fuel combustion strategies such as Reactivity Controlled Compression Ignition (RCCI) have been developed. Reactivity stratification of the auto-igniting mixture is thought to be responsible for the increase in allowable engine load compared to other LTC combustion modes such as Homogenous Charge Compression Ignition (HCCI). The current study investigates the effect of ethanol intake fuel injection on in-cylinder formaldehyde formation and stratification within an optically accessible engine operated with n-heptane direct injection using optical measurements and zero-dimensional chemical kinetic models. Images obtained by Planar Laser Induced Fluorescence (PLIF) of formaldehyde using the third harmonic of a pulsed Nd:YAG laser indicate an increase in formaldehyde heterogeneity as measured by the fluorescence signal standard deviation. The experimental observations are complemented by a discussion regarding definitions of “reactivity”.