Influence of injection timing on performance, combustion and emission characteristics of Jatropha biodiesel engine T. Ganapathy a,⇑ , R.P. Gakkhar b , K. Murugesan b a St.Anne’s College of Engineering & Technology, Anguchettypalayam, Panruti (Tk), Cuddalore (Dt), TN, India b I. C. Engines Lab., Mechanical & Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand, India article info Article history: Received 20 June 2010 Received in revised form 6 May 2011 Accepted 11 May 2011 Keywords: Injection timing Jatropha biodiesel Performance Combustion Emission abstract The study of effect of injection timing along with engine operating parameters in Jatropha biodiesel engine is important as they significantly affect its performance and emissions. The present paper focuses on the experimental investigation of the influence of injection timing, load torque and engine speed on the performance, combustion and emission characteristics of Jatropha biodiesel engine. For this purpose, the experiments were conducted using full factorial design consisting of (3 3 ) with 27 runs for each fuel, diesel and Jatropha biodiesel. The effect of variation of above three parameters on brake specific fuel con- sumption (BSFC), brake thermal efficiency (BTE), peak cylinder pressure (P max ), maximum heat release rate (HRR max ), CO, HC, NO emissions and smoke density were investigated. It has been observed that advance in injection timing from factory settings caused reduction in BSFC, CO, HC and smoke levels and increase in BTE, P max , HRR max and NO emission with Jatropha biodiesel operation. However, retarded injection timing caused effects in the other way. At 15 N m load torque, 1800 rpm engine speed and 340 crank angle degree (CAD) injection timing, the percentage reduction in BSFC, CO, HC and smoke levels were 5.1%, 2.5%, 1.2% and 1.5% respectively. Similarly the percentage increase in BTE, P max , HRR max and NO emission at this injection timing, load and speed were 5.3%, 1.8%, 26% and 20% respectively. The best injection timing for Jatropha biodiesel operation with minimum BSFC, CO, HC and smoke and with max- imum BTE, P max , HRR max is found to be 340 CAD. Nevertheless, minimum NO emission yielded an opti- mum injection timing of 350 CAD. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction The world’s two energy crises in the years 1973 and 1978 [1], rapid depletion of fossil fuel reserves, exponential hike in crude oil prices due to global political turmoil and increasing concern on global environmental protection norms, etc., revived the impor- tance of vegetable oil or biodiesel use in diesel engines. Since then serious efforts have been made to replace or substitute diesel fuel by alternative fuels. Among various alternative fuels the biodiesel has been identified as versatile fuel for diesel engines applications. In any country at present biodiesel is made from different variety of feed stocks that are available and cultivable domestically [2]. The environmental and economic concerns (Kyoto Protocol) have also prompted resurgence in the use of biodiesel throughout the world. In 1991, the European Community (EC), proposed a 90% tax reduction for the use of biofuels, including biodiesel. Many countries around the world have passed legislations requiring die- sel to contain a minimum percentage of biofuels. The best record is held by the Czech Republic, which insists on 100% biofuel use for transportation [3]. Today many countries including India world- wide produce and use biodiesel. Since India does not produce enough edible oil for its culinary needs, a Planning Commission committee on development of biofuel, which submitted its report in 2003, noted that biodiesels in this country have to be made from non-edible oil seeds. More than 75 non-edible feed stocks have been identified in India, whose fuel characteristics were found to be within the specification of biodiesel standard of USA, Germany and European Standard Organi- zation [4–6]. Although Pongamia Pinnata (Karanja Curcas), Neem, Rubber, Rice Bran, Castor and Jatropha Curcas have been studied experimentally, the last one has been thought to be promising choice for production of economically feasible biodiesel for India. Experimental studies carried out in various countries including India show that several parameters affect the performance, com- bustion and emission characteristics of diesel engine [7–23]. However the effect of injection timing and the operating param- eters is quite significant and their effect on engine performance has been widely studied by the researchers. The effect is even adverse sometimes when the engine is tried with some alterna- tive fuels, such as Jatropha biodiesel due to its physico-chemical 0306-2619/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.apenergy.2011.05.016 ⇑ Corresponding author. Tel.: +91 9486692624. E-mail address: tganappathi@yahoo.co.in (T. Ganapathy). Applied Energy 88 (2011) 4376–4386 Contents lists available at ScienceDirect Applied Energy journal homepage: www.elsevier.com/locate/apenergy