Spark ignition to homogeneous charge compression ignition mode transition study: a new modelling approach

Abstract

A hybrid spark ignition/homogeneous charge compression ignition engine model for simulating the spark ignition to homogeneous charge compression ignition transition in a four-cylinder gasoline engine is presented. This hybrid spark ignition/homogeneous charge compression ignition model has been developed to provide help in understanding the complicated spark ignition to homogeneous charge compression ignition transition process and in tackling the control problems associated with it. The model was built in Matlab/Simulink, coupled with a tabulated stochastic reactor model and a detailed chemical kinetics mechanism. Typical computational times encountered in the simulation using this model were of the order of seconds for one engine cycle. The model was validated in steady-state spark ignition and homogeneous charge compression ignition operation by experimental data, followed by model-based parametric studies in homogeneous charge compression ignition operation. Then, a spark ignition to homogeneous charge compression ignition mode transition was simulated using the model. The results showed good agreement with experimental data, in terms of cylinder pressure, combustion phasing, air/fuel ratio, residual gas fraction and nitrogen oxides. The high computational efficiency and relatively high accuracy of this model enable its good applicability in experimental design and controller development, and potential use in hardware-in-loop applications.