18 Experimental Studies on the Effect of Threaded - Piston Geometry on Combustion and Emissions of Diesel Engine Fuelled with Simorouba Bio-Diesel Lava K.R. 1 , C.R. Rajashekhar 2 , Vilas Watwe 3 1 Lecturer, Department of Mechanical Eng., S.T.J. Institute of Technology, Ranebennur., India 2 Deptt. of Mechanical Engg., Mangalore Institute of Technology and Engineering, Moodabidri. 3 Dept.of Mechanical Engg, Adichunchanagiri Institute of Technology, Chikmagalur, Karnataka, India ABSTRACT In the present scenario bio-diesels have received a lot of attention as an alternate vehicular fuel. But the properties of bio-diesels are not the same as diesel fuels especially their high viscosity and low volatility. Also the bio-diesels have very poor atomization characteristics due to decreased cone angle during fuel injection. This paper relates the modification of engine combustion chamber design, for inducing turbulence to improve the combustibility of combustible mixture. A survey of literature shows that experimental studies have not been done on a threaded piston for evaluating influence on the combustion and emission characteristics using diesel blends as well. The objective of this work is to study the effect of combustion chamber geometry on combustion and emissions of a bio-diesel (Simorouba) fuelled threaded piston diesel engine. It has been noticed that for the engine under consideration with threaded piston gives optimum performance. This work is to study the effect of threaded piston on combustion, performance and emissions of a bio- diesel (Simorouba) fuelled threaded piston diesel engine. It has been noticed that for the engine under consideration with threaded piston gives optimum performance. NOMENCLATURE TDC : Top Dead Centre BTDC : Before Top Dead Centre UBHC : Unburned Hydrocarbon NO X : Oxides Of Nitrogen CO : Carbon Monoxide CI : Compression Ignition PME : Poly Methyl Ester CFD : Computational Fluid Dynamics SF C : Specific Fuel Consumption CV : Calorific Value CR : Compression Ratio IP : Injection Pressure Bth : Brake Thermal Efficiency BP : Brake Power International Journal of Research in Mechanical Engineering Volume-2, Issue-3, May-June, 2014, pp. 18-24, © IASTER 2014 www.iaster.com, ISSN Online:2347-5188 Print: 2347-8772