EXPERIMENTAL INVESTIGATION ON COMBUSTION AND EMISSION CHARACTERISTICS OF MODIFIED PISTON IN AN IDI DIESEL ENGINE FUELED WITH ETHYL ALCOHOL M.Parthasarathy 1) , J.Isaac JoshuaRamesh Lalvani 2) , E.Prakash 3) , S.Jayaraj 4) , K.Annamalai 5) 1, 2 Research Scholar, Dept. of Automobile Engineering, Anna University, Chennai, India. 3 Master of Engineering, Dept. of Automobile Engineering, Anna University, Chennai, India. 4 Associate Professor, Dept. of Automobile Engineering, Anna University, Chennai, India. 5 Assistant Professor, Dept. of Automobile Engineering, Anna University, Chennai, India. a msarathymech@gmail.com, b isaaclalvani@yahoo.com Keywords: Ethyl alcohol, Squish, Emissions, Combustion Abstract.Compression ignition engines with ethyl alcohol as a fuel are associated with some problems. Because of ethyl alcohol has high self ignition temperature. It can be used in compression engine by hot surface ignition method which is used to resolve the ignition of the fuel. The modification of the engine is carried out in such a way that a pre combustion chamber is designed in engine head with a provision for heat plug is made on the pre combustion chamber. A piston with squish plate is designed and thermally analyzed. The squish piston helps for attaining better homogeneous mixture than conventional piston. Thus the better combustion is obtained with the squish piston resulting with higher adiabatic flame temperature than the conventional piston. When air is inducted into the combustion chamber it is exposed to high temperature. Modifications for pure ethyl alcohol made significant improvement in thermal efficiency, torque and reduction in specific fuel consumption of an engine.The results exhibit a path toward ethyl alcohol has an effective alternative to conventional diesel engines. INTRODUCTION In recent days it was shown that the fast growing need of investigations and technical and development to use alternative fuels in the present power system. Both in vehicular and stationary application a substantial number of different approaches can be seen in many places in the world [1]. The single most important force propelling system fuels development is the rapid escalation of prices of oil on the international crude market and continued uncertainty regarding future prices in addition to the rapid drain by way of consumption [2]. Therefore the whole world has little choice but to pursue alternative fuel. Clearly the need in most countries is to develop substitutes for oil or oil-derived products. However what form of fuel substitute is most appropriate will depend on several factors specific to a given country [3, 4]. Alcohols are the most preferred alternative fuels, because that can be produced from various resources [5]. There are several methods by which alcohols can be used in diesel engines. Ethyl alcohol is one of the best fuels to replace the diesel in C.I engines. Sugar cane, sorghum, corn barley are raw materials of the ethyl alcohol. Since 1970’s the usage of ethyl alcohol in the diesel engines have been studied [6-8]. The early experimentations were focused on reduction of CO 2 life cycle and particle levels. Ethyl alcohol is an assured oxygenated fuel. In compression ignition engines the ethyl alcohol can be used in the form of alcohols-diesel blend (mixture of the fuels prior to injection) fumigation of alcohols (injection of alcohols into the intake air charge), alcohols-diesel emulsion (emulsifier can be used to mix the fuels) and dual injection (each fuel has separate injection systems) [9-11].The cold starting problems avoided by the hot surface assisted ignition concept. This concept has been introduced particularly for the low cetane fuels like ethyl alcohol. The hot surface provides sufficient local ignition condition and establishes a stable diffusion flame[12, 13]. The geometry of the piston is an act important role on heat transfer of diesel engine. These types of pistons are generally used in direct injection engines. The air and fuel mixes very well in a squish model piston than a conventional type of piston. The main function of squish in a piston is creating turbulence [14]. Advanced Materials Research Vols. 984-985 (2014) pp 873-877 Submitted: 25.04.2014 Online available since 2014/Jul/16 at www.scientific.net Accepted: 27.04.2014 © (2014) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMR.984-985.873 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, www.ttp.net. (ID: 103.10.197.154-03/01/15,12:56:49)