Computational fluid dynamics studies on the influence of fuel variability on diesel engine operation

Abstract

Increasing environmental and economic concerns have long motivated research into improving engine performance and efficiency. Computational Fluid Dynamics (CFD) simulations containing chemical reactions to describe combustion chemistry are a critical tool in engine development; however, chemical kinetic mechanisms, which describe the essential ignition and combustion processes in an engine, tend toward the complex and detailed as they become more accurate in modeling the elementary chemical interactions. Such complex chemical mechanisms are computationally expensive – implementing them in a realistic applied simulation, such as combustion in a diesel engine, causes that simulation to become computationally prohibitive. Here, CFD simulations of spray ignition and combustion in a constant volume environment and a diesel engine are demonstrated using global and reduced reaction kinetics models. These simulations are shown to be in reasonably good quantitative agreement with experiment and very good agreement for the variation of spray ignition delay with fuel variation.