A control - oriented model of combustion process in a HCCI diesel engine

Abstract

Homogeneous Charge Compression Ignition is a promising concept for achieving low emissions at partload operations. This technique can be successfully applied to traditional Direct Injection Diesel engines with low extra costs and no modification to the DI system by performing the mixture formation in the intake manifold.The present work describes the development of a controloriented model for the study of the combustion process in a HCCI Diesel engine with external mixture formation. The model is based on a first-law thermodynamic analysis of in-cylinder processes in order to identify the influence of the main control parameters on HCCI auto-ignition. The combustion process is modeled through the definition of a gross heat release rate, avoiding a detailed description of the chemical reactions that could increase the complexity and the computation time.The model is then validated against experimental data obtained on a Diesel engine equipped with an external fuel atomizer. The satisfactory agreement obtained and the low calibration effort make the model a useful tool for the development of applications related to HCCI engine control and diagnostics.

Double-Wiebe function: An approach for single-zone HCCI engine modeling

“…This leads to a ''double-Wiebe function'' model. Canova et al [5] used a triple-Wiebe function model for diesel HCCI but with gasoline, the initial cool flame heat release is not evident as a separate feature and a double-Wiebe function is thought to be sufficient. The utility of the double-Wiebe function modification by comparing the pressures calculated using the standard and double-Wiebe function methods with experimental pressure data obtained from a Hydra HCCI Engine is tested.…”

“…A key characteristic of HCCI is the rapid burning of the fuel/air mixture because of autoignition occurring almost simultaneously around the cylinder. Results from numerous researches on HCCI combustion have been published [1][2][3][4][5][6][7][8][9][10][11][12][13][14] in recent years. HCCI engines have been shown to achieve extremely low levels of nitrogen oxide emissions (NO x ) without catalytic converters.…”

Development of a control-oriented model to optimise fuel consumption and NOX emissions in a DI Diesel engine

“…Inputs selection: once the reference operating point was selected, in order to design the parametric study [30,35,36], the most influential input variables and 7 their variations were chosen. For this purpose, a preliminary simple effect study was carried out.…”

Effect of Different Heat Transfer Models on a Diesel Homogeneous Charge Compression Ignition Engine

“…Computational fluid dynamics (CFD) approaches are used to obtain more accurate results at the expense of computational costs, while thermodynamics approaches are suitable for fast results that are comparable to experimental results (Babajimopoulos, Lavoie, & Assanis, 2003;Canova et al, 2005). This paper uses the thermodynamics approach to investigate the effect of different heat transfer models on an HCCI engine.…”