TITLE:
Influence of Combustion Chamber Design Parameters and Intake Environments on Spark Ignition Engine Performance and Exhaust Gas Emission
AUTHORS:
Ali S. Al-Shahrany, Ahmed S. A. Hassan
KEYWORDS:
Spark Ignition Engine, Four Stroke, Combustion Chamber, Crank Angle, Emission
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.12 No.6,
June
22,
2022
ABSTRACT: In the present paper, the effect of the combustion
chamber design parameters on the improvement of combustion efficiency (the heat
generated inside the combustion chamber) and the enhancement in the pollution
rates (heat emissions) from a four-stroke, spark-ignition engine has been
studied experimentally and theoretically. Two different programs, Gaseq and Ansys,
were used to simulate the effect of the combustion chamber shape, turbulent
kinetic energy, intake temperature, intake pressure, parity ratio, compression
ratio, and engine speed on reducing specific fuel consumption in the engine,
reducing carbon dioxide emissions, and increasing overall engine efficiency.
The results showed increasing the intake temperature increased the amount of
heat produced in the combustion chamber. This leads to increases in the overall
efficiency of the engine, but leads to increasing the carbon dioxide and nitrogen oxide
emissions. Increasing the intake pressure has a positive effect on the
combustion temperature and pressure, but it has a negative effect on carbon
dioxide and nitrogen oxides. Raising the pressure ratio improved the overall
efficiency of the engine by increasing the combustion heat, but increasing specific
fuel consumption and emissions. Also, increasing the engine speed above the
permissible limit has an adverse effect on the spraying speed due to the piston
speed being higher than the flame speed, which leads to a reduction in the
engine brake torque. An increase in the compression ratio leads to higher fluid
pressure and output capacity, but combustion methods occur. An increase in the
kinetic energy of the turbulence leads to good combustion. A bowl in a piston
has the highest rate of rotation and rotation compared to flat and
hemispherical pistons. That is, the design of the cylinder head of this type
leads to an improvement in the combustion efficiency and thus the efficiency of
the engine.