| In response to increasingly stringent engine emissions regulation, three dimensional in-cylinder combustion modeling is increasingly being used as a tool to optimize the combustion process and reduce the cost of experimental testing. Due to the complexity of the physical and chemical interactions involved in the in-cylinder combustion process, the engine combustion model consists of numerous sub-models developed under pre-defined initial and boundary conditions requiring further model calibration depending on different engine applications. Fuel surrogates, one of those sub-models developed for different combustion applications, may not capture all the behavior when applied to the varying temperature-pressure conditions present in a compression ignition engine.;In this work a set of optical and global measurements are chosen to experimentally validate a fuel surrogate using an optically accessible compression ignition engine. In addition, to provide a means of directly comparing three-dimensional engine combustion CFD predictions to in- cylinder optical measurements, another aim of this work is to model light emission during the compression ignition engine combustion process. Major excited state species (CH*, CH2O*, OH*, CO2* and C2*) are modeled to study UV chemiluminescence signal observed in the in-cylinder hydrocarbon fuel oxidation process. A novel approach to validate multi-dimensional combustion CFD results is presented. The classic two-color method theory is further developed by analysis of the natural soot luminosity on a McKenna Flat Flame Burner. Spectral and Coherent anti-Stokes Raman Spectroscopy (CARS) measurements are used to propose a value of alpha in the soot emissivity model. |
