Combustion model reduction for diesel engine control design

Abstract

The subject of this work is the derivation of a simulation model for premixed charge compression ignition (PCCI) combustion that can be used in closed-loop control development. For the high-pressure part of the engine cycle, a detailed three-dimensional computational fluid dynamics model is reduced to a stand-alone multi-zone chemistry model. This multi-zone chemistry model is extended by a mean value model accounting for the gas exchange losses. The resulting model is capable of describing PCCI combustion with stationary exactness, and is at the same time very economic with respect to computational costs. The model is further extended by the identified system dynamics that influence the stationary inputs. For this purporse, a Wiener model is set up that uses the stationary model as a non-linear system representation. In this way, a dynamic non-linear model for the representation of the controlled plant diesel engine is created.