A Quasi-Dimensional NO
x
Emission Model for Spark Ignition Direct Injection (SIDI) Gasoline Engines
2013-01-1311
A fundamentally based quasi-dimensional NOx emission
model for spark ignition direct injection (SIDI) gasoline engines
was developed. The NOx model consists of a chemical
mechanism and three sub-models. The classical extended Zeldovich
mechanism and N₂O pathway for NOx formation mechanism
were employed as the chemical mechanism in the model. A
characteristic time model for the radical species H, O and OH was
incorporated to account for non-equilibrium of radical species
during combustion. A model of homogeneity which correlates
fundamental dimensionless numbers and mixing time was developed to
model the air-fuel mixing and inhomogeneity of the charge. Since
temperature has a dominant effect on NOx emission, a
flame temperature correlation was developed to model the flame
temperature during the combustion for NOx
calculation.
Measured NOx emission data from a single-cylinder
SIDI research engine at different operating conditions was used to
validate the NOx model. The effects of fuel injection
timing, injection pressure, spark timing, overall engine AFR, and
intake temperature on NOx emission were examined and
well captured by the model. Comparison of all the NOx
emission data with the model indicates that the NOx
model is a good predictive tool for NOx emissions in
SIDI engines.
Citation: Gong, J. and Rutland, C., "A Quasi-Dimensional NOx Emission Model for Spark Ignition Direct Injection (SIDI) Gasoline Engines," SAE Technical Paper 2013-01-1311, 2013, https://doi.org/10.4271/2013-01-1311. Download Citation
Author(s):
Jian Gong, Christopher Rutland
Affiliated:
University of Wisconsin-Madison
Pages: 13
Event:
SAE 2013 World Congress & Exhibition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
Modeling of SI and Diesel Engines, 2013-SP-2344
Related Topics:
Nitrogen oxides
Fuel injection
Air / fuel ratio
Combustion and combustion processes
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