Analysis of the HCCI combustion of a turbocharged truck engine using a Stochastic Reactor Model

Homogeneous Charge Compression Ignition (HCCI)engines arouse great interest due to their high thermalefficiency and very low emissions of nitrogen oxides(NOx) and particulates. Critical issue of the HCCIcombustion is the control of the engine since thecombustion process is mostly dominated by chemicalkinetics. Therefore the accurate assessment of thechemical kinetic is fundamental in numerical simulation ofthis kind of engines.Experimentally it has been demonstrated that even inHCCI engine the charge within the cylinder is not fullyhomogeneous, but many quantities, such as temperature,density and equivalence ratio, vary along the combustionchamber. These inhomogeneities influence thecombustion process and yield the homogeneous reactormodel to be not completely adequate to simulate HCCIcombustion.This paper focuses on the use of a stochastic rectormodel in order to account for temperatureinhomogeneities in the numerical simulation of the HCCIcombustion. Moreover, the chemical kinetic code hasbeen coupled to GT – Power Code, a 1-D fluid –dynamics code, in order to accurately simulate theoperation of a turbocharged truck engine.