Year: 2017 Volume: 1 Issue: 2 Page: 53-58
THE EFFECTS OF DIFFERENT COMPRESSION RATIOS ON THE PERFORMANCE AND EMISSIONS OF A SPARK IGNITION ENGINE WITH A NEW COMBUSTION CHAMBER
ABDURRAHMAN DEMİRCİ, HÜSEYİN EMRE DOĞAN, ÖMER CİHAN, OSMAN AKIN KUTLAR, RAFIG MEHDIYEV
Nowadays, there are different ideas about the future of internal combustion engines. Despite the thoughts about internal combustion engines old technology, there have been many new researches about internal combustion engines. Reduction of fuel consumption and improving of the exhaust emissions are the main research topics in the spark ignition engines in the present day. The aim of this paper is to examine experimentally the effect of different compression ratios on the performance and exhaust emissions of a single cylinder, which is water cooled, port fuel injection and spark ignition engine. A new combustion chamber geometry was designed and three same combustion chamber geometries with different compression ratios were manufactured. It is expected from the combustion chamber shapes to run the engine properly in the lean mixtures. However, it is expected of some improvement in fuel consumption and reduction of NO emissions. The experiments were tested at seven different excess air coefficients (1.0, 1.10, 1.20, 1.30, 1.45, 1.60 and 1.70), different compression ratios (10.5, 12 and 14), wide open throttle (WOT) and the constant speed, 2500 rpm. The fuel quantity, spark advance and throttle condition were controlled electronically using an engine control unit (ECU). With the running of engine with lean mixtures, NO emissions are reduced. When NO emissions are reduced, it will decrease the need for NO catalyst. Experimental results show that increasing of compression ratio and decreasing of spark advance leaded to decreasing of NO emissions at nearly mean effective pressure values.
Anahtar Kelimeler (Keywords): Gasoline Engine, Chamber Geometry, Lean Burn, NO Reduction