A Monte Carlo Based Turbulent Flame Propagation Model for Predictive SI In-Cylinder Engine Simulations Employing Detailed Chemistry for Accurate Knock Prediction

Event
SAE 2012 International Powertrains, Fuels & Lubricants Meeting
Authors Abstract
Content
This paper reports on a turbulent flame propagation model combined with a zero-dimensional two-zone stochastic reactor model (SRM) for efficient predictive SI in-cylinder combustion calculations. The SRM is a probability density function based model utilizing detailed chemistry, which allows for accurate knock prediction. The new model makes it possible to - in addition - study the effects of fuel chemistry on flame propagation, yielding a predictive tool for efficient SI in-cylinder calculations with all benefits of detailed kinetics.
The turbulent flame propagation model is based on a recent analytically derived formula by Kolla et al. It was simplified to better suit SI engine modelling, while retaining the features allowing for general application. Parameters which could be assumed constant for a large spectrum of situations were replaced with a small number of user parameters, for which assumed default values were found to provide a good fit to a range of cases. Only one parameter, the turbulence intensity, needed tuning to obtain excellent agreement for various cases. The laminar flame speed is obtained from a laminar flame speed library generated using detailed chemistry.
The flame development was calculated from the turbulent flame speed under the assumption of a spherical flame. A Monte Carlo geometry calculation was applied to cater for arbitrary cylinder geometries and spark plug positions, modelling the geometrical properties of the flame with high precision. In later stages of the project, a polygon based description of the flame surface was used, to achieve faster computational times than those of the Monte Carlo model.
Meta TagsDetails
DOI
https://doi.org/10.4271/2012-01-1680
Pages
11
Citation
Bjerkborn, S., Frojd, K., Perlman, C., and Mauss, F., "A Monte Carlo Based Turbulent Flame Propagation Model for Predictive SI In-Cylinder Engine Simulations Employing Detailed Chemistry for Accurate Knock Prediction," SAE Int. J. Engines 5(4):1637-1647, 2012, https://doi.org/10.4271/2012-01-1680.
Additional Details
Publisher
Published
Sep 10, 2012
Product Code
2012-01-1680
Content Type
Journal Article
Language
English