Society of Automotive Engineers, Inc., 2004. — 11 p.Abstract
This paper reports the development of an improved model of diesel combustion and NO emissions, based on a modified eddy dissipation concept
(EDC), and its implementation into the KIVA-3V multi-dimensional simulation. Compared to the commonly used eddy break-up (EBU) model, the
EDC model allows more realistic representation of the thin sub-grid scale reaction zone as well as the small-scale molecular mixing processes, thereby
achieving higher fidelity of the simulation. Realistic chemical kinetic mechanisms for n-heptane combustion and NOx formation processes
are fully incorporated. In addition, a transition model based on the normalized fuel mass fraction is successfully implemented to reproduce ignition and
combustion processes accurately. Simulations are performed for various engine speeds, injection timings, and EGR content, and the results for the
basic engine performance agree well with the experimental data. The predictions for NO concentration also show a consistent trend with
experiments, demonstrating the improved predictive capability of the present model for diesel engine design and development.
