Piston Fuel Film Observations in an Optical Access GDI Engine
2001-01-2022
05/07/2001
- Event
- Content
- A gasoline direct injection fuel spray was observed using a fired, optical access, square cross-section single cylinder research engine and high-speed video imaging. Spray interaction with the piston is described qualitatively, and the results are compared with Computational Fluid Dynamics (CFD) simulation results using KIVA-3V version 2. CFD simulations predicted that within the operating window for stratified charge operation, between 1% and 4% of the injected fuel would remain on the piston as a liquid film, dependent primarily on piston temperature. The experimental results support the CFD simulations qualitatively, but the amount of fuel film remaining on the piston appears to be under-predicted. High-speed video footage shows a vigorous spray impingement on the piston crown, resulting in vapor production. The primary GDI combustion process, a roughly premixed flame, is followed by a turbulent diffusion flame or “pool fire” in the region of the liquid film, once the piston is warm enough to produce vapor at a sufficient rate.
- Pages
- 15
- Citation
- Karlsson, R., and Heywood, J., "Piston Fuel Film Observations in an Optical Access GDI Engine," SAE Technical Paper 2001-01-2022, 2001, https://doi.org/10.4271/2001-01-2022.