Abstract: (25355 Views)
Porous media has interesting features in compared with free flame combustion due to the extended of the
lean flammability limits and lower emissions. Advanced new generation of internal combustion (IC)
engines are expected to have far better emissions levels both gaseous and particulate matter, at the same
time having far lower fuel consumption on a wide range of operating condition. These criteria could be
improved having a homogeneous combustion process in an engine. Present work considers simulation of
direct fuel injection in an IC engine equipped with a chemically inert porous medium (PM), having
cylindrical geometry that is installed in cylinder head to homogenize and stabilize the combustion process.
A numerical study of a 3D model, PM engine is carried out using a modified version of the KIVA-3V code.
Since there is not any published material for PM-engines in literature, the numerical results for combustion
waves propagation within PM are compared with experimental data available in the literature for a lean
mixture of air and methane under filtration in packed bed, the accuracy of results are very promising. For
PM-engine simulation the methane fuel is injected directly through a hot PM which is mounted in cylinder
head. Therefore volumetric combustion occurs as a result within PM and in-cylinder. The effects of
injection timing on mixture formation, pressure and temperature distribution in both phases of PM and incylinder
fluid together with combustion emissions such as CO and NO are studied in detail for an important
part of the cycle.