Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
Characterization of the flame development in the first cycles of operation in a spark ignition engine from the injection modes PFI and DI for ethanol and gasoline
Submission Author:
Maycon Silva , SP
Co-Authors:
Maycon Silva, Pedro Lacava
Presenter: Maycon Silva
doi://10.26678/ABCM.COBEM2019.COB2019-0743
Abstract
The characteristics of the first firing cycle were experimentally investigated for a single cylinder research engine PFI-SI and DI-SI with optical access, fueled with anhydrous ethanol and gasoline. Due to the fact the worse combustion during the initiation of an engine results in an increase of misfiring events and unstable combustion process, it is necessary to better understand the flame behavior and spatially propagation to improve the combustion especially in the start of the engine. High spatial resolution cycle resolved digital imaging, in the visible and UV spectral range was used to characterize the flame front propagation. A post-processing routine was developed to evaluate flame areas and global morphology characteristics to have a detail understanding of the flame behavior in the combustion chamber. The engine was fueled with ethanol (E100) and gasoline (G100). It was operated at 900 rev/min to study the behavior of the combustion process with low turbulent effects. The injection duration was set to a value of stoichiometric mixture when stable operation is reach. The results for the PFI suggest an increase in the flame area with the increase in the cycles of operation. In addition, a decrease in the flame deformation was measured. Absence of flame at the beginning of the process is also observed, followed by unstable combustion. For the DI mode, combustion reaches results close to the permanent thermal regime from the beginning, however with great cyclic variability.
Keywords
Combustion, First Cycles, SI Engines, ethanol, Gasoline, Direct injection, PFI
