Numerical Simulation of Spark Ignition Engines

Abstract

Optimization processes for internal combustion engines requires application of advanced development tools. In addition to experimental method, numerical calculations are needed in order to obtain an insight into the complex phenomena in-cylinder processes. This chapter was organized for advances in computational fluid dynamic, heat transfer, and chemical reactions as applied to internal combustion engines. It provided an opportunity for specialists in the area of modeling flow and combustion in SI engines to provide powerful computational tools in the area of endeavor surrounding fluid dynamics. We examine computations for reactive flows in general with computational combustion in particular. In reactive flows, the conservation equations for chemical species are added to the Navier Stokes system of equations. This addition also requires a modification of the energy equation. Furthermore, the sensible enthalpy is coupled with the chemical species, which contributes to the heat source and diffusion of species interacting with temperature. Thus, the chemically reactive flows and combustion require significant modifications of not only the governing equations, but also the existing computational methods discussed in this chapter. The aims of these computational developments have been: (1) to develop reliable engine tools for predicting the flow, temperature, etc fields; (2) to reduce the cost of current experiments that are used for most of the relevant engineering design; (3) to allow for a better understanding of physiochemical processes involved. Details of turbulent fluid motion in engines are required for determining combustion, thermal efficiencies, and level of emissions for development of cleaner, less noisy, and more efficient engines for a variety of designs and fuels.