EARLY STAGES OF COMBUSTION IN INTERNAL-COMBUSTION ENGINES USING LINKED CFD AND CHEMICAL-KINETICS COMPUTATIONS AND ITS APPLICATION TO NATURAL-GAS BURNING ENGINES
D. Yossefi et al., EARLY STAGES OF COMBUSTION IN INTERNAL-COMBUSTION ENGINES USING LINKED CFD AND CHEMICAL-KINETICS COMPUTATIONS AND ITS APPLICATION TO NATURAL-GAS BURNING ENGINES, Combustion science and technology, 130(1-6), 1997, pp. 171-200
The paper describes a numerical model for the early stages of combusti
on in Natural Gas engines using linked CFD and detailed chemical kinet
ics. The importance of such a combustion device stems from the charact
eristics of natural gas which make it an attractive near-term solution
for the automotive emissions problem. The 3-D simulation, which incor
porates a chemical model, turbulence model and ignition model is taken
under engine-like conditions. This is achieved by coupling the numeri
cal codes KIVA II, developed to solve the transient equations of conse
rvation of turbulent chemically reacting mixture of ideal gases, CHEMK
IN II, designed to facilitate simulations of elementary chemical react
ions in flowing systems, TRANSPORT, used for the evaluation of gas-pha
se multicomponent transport properties, and LIOR - a linking code. The
numerical tool has predictive capability for combustion behaviour und
er various conditions, an ability to interpret observed combustion phe
nomena and ability to guide the design of better natural gas engines.
A justification of the validity of the approach is discussed in terms
of the asymptotic structure of the methane-air flame. The early states
of the combustion event are described in some detail and two specific
studies are briefly reported, that of the effects of various ignition
source types for natural gas burning domestic vehicle engines, and th
at of the effects of variation in composition of the natural gas.