Zero-Dimensional Heat Release Modeling Framework for Gasoline Compression-Ignition Engines with Multiple Injection Events

摘要

A zero-dimensional heat release model was developed for compression ignition engines. This type of model can be utilized for parametric studies, off-line optimization to reduce experimental efforts as well as model-based control strategies. In this particular case, the combustion model, in a simpler form, will be used in future efforts to control the combustion in compression ignition engines operating on gasoline-like fuels. To allow for a realistic representation of the in-cylinder combustion process, a spray model has been employed to allow for the quantification of fuel distribution as well as turbulent kinetic energy within the injection spray. The combustion model framework is capable of reflecting premixed as well as mixing controlled combustion. Fuel is assigned to various combustion events based on the air-fuel mixture within the spray. The mixing controlled combustion consists of two separate combustion events; one occurring within the fuel spray, which is characterized by rich fuel mixtures with a substantial level of turbulent kinetic energy and high combustion rates; the other one describes moderate combustion rates of lean fuel mixtures with less turbulent kinetic energy. Model constants were calibrated against experimental data from a 12.4L heavy-duty compression ignition engine operated on gasoline for various sweeps at 14bar BMEP and mostly at an engine speed of 1038rpm. A maximum prediction error in combustion phasing of 1.3CAD was found across the 30 calibrated sample points.