Reductions of Bio-Diesel Exhaust Emissions through Engine Combustion Chamber Design Modifications — An Experimental Study

Increased demand and production in all segments of the automotive industry has driven the nation to impose stringent emission norms for automobile engines. At this juncture, bio-diesel has sufficient attraction as vehicular fuel. But the properties of bio-diesels are not the same as diesel fuels, including high viscosity and low volatility. Due to this inherent problem it exhibits poor atomization, which results in incomplete combustion and increased exhaust emissions. This naturally implies that automotive designers have to focus their research more on engine emissions while at the same time not compromising on power development. This has put enormous pressure on automotive industry to design the engine efficiently and economically to compete with the global market. This paper relates the modification of engine combustion chamber design, for inducing turbulence to improve the combustibility of combustible mixture of karanja bio-diesel and to reduce the exhaust emissions. The modification includes the tri-chambered piston and twisting blade pistons. In the present work the emission characteristics of modified piston engine are compared with the standard piston engine. It was observed that the CO and UBHC emissions can be effectively reduced with tri-chambered piston engine.