This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Diesel Cylinder Charge Properties: Feed-Forward Control and Cycle-by-Cycle Analysis Using an In-Cylinder Gas Sampling System
ISSN: 1946-3936, e-ISSN: 1946-3944
Published April 12, 2011 by SAE International in United States
Citation: Darlington, A., Collings, N., and Glover, K., "Diesel Cylinder Charge Properties: Feed-Forward Control and Cycle-by-Cycle Analysis Using an In-Cylinder Gas Sampling System," SAE Int. J. Engines 4(1):861-873, 2011, https://doi.org/10.4271/2011-01-0709.
Common-rail fuel injection systems on modern light-duty diesel engines are effectively able to respond instantaneously to changes in the demanded injection quantity. In contrast, the air-system is subject to significantly slower dynamics, primarily due to filling/emptying effects in the manifolds and turbocharger inertia. The behavior of the air-path in a diesel engine is therefore the main limiting factor in terms of engine-out emissions during transient operation. This paper presents a simple mean-value model for the air-path during throttled operation, which is used to design a feed-forward controller that delivers very rapid changes in the in-cylinder charge properties. The feed-forward control action is validated using a state-of-the-art sampling system that allows true cycle-by-cycle measurement of the in-cylinder CO₂ concentration.