R.T. Sarath Babu et al., International Journal of Advanced Engineering Technology E-ISSN 0976-3945 Int J Adv Engg Tech/Vol. VII/Issue II/April-June,2016/1188-1190 Research Paper EVALUATION OF MAHUA OIL BIODIESEL AND ITS BLENDS ON PERFORMANCE AND EMISSION CHARACTERISTICS OF DIESEL ENGINE R.T. Sarath Babu 1 , M. Kannan 2 , P. Lawrence 3 Address for Correspondence 1 Department of Mechanical Engineering, Rajiv Gandhi College of Engineering, Sriperumbudur, India 2 Department of Mechanical Engineering, KCG College of Technology, Chennai, India 3 Department of Mechanical Engineering, PSV College of Engineering & Technology, Krishnagiri, India. ABSTRACT Diesel engines are major contributors of many air polluting exhaust gasses such as carbon monoxide, unburned hydrocarbons, oxides of nitrogen and other harmful compounds. It has been shown that formation of these air pollutants can be significantly reduced by using biodiesel as alternate fuel. This study presents the results of experimental investigation on the effects mahua oil biodiesel and its blends on performance and emission characteristics of diesel engine. Biodiesel from mahua oil was prepared through transesterification process with low molecular weight alcohols and sodium hydroxide. Experiments were conducted to evaluate the performance and emission parameters of a single cylinder, four stroke, water cooled, direct injection diesel engine. The results obtained from all the fuel blends were analyzed and compared with neat diesel operation. KEYWORDS: Mahua oil, Biodiesel, Alternate fuel, Diesel engine. INTRODUCTION Fossil fuels such as petroleum, natural gas and coal have been meeting most industrial and commercial demands for relatively low cost, high energy density, transportable fuels for decades. However, being the main source of transportation fuels, petroleum is estimated to be running out within 50 years due to the limited storage under the stratum [1-3]. In addition, burning fossil fuels generates pollutant emissions and greenhouse gases (primarily concerned with carbon dioxide emissions) [4]. In the above context, alternate fuels based on vegetable oils represent a valid alternative to fossil fuels in internal combustion engines [5]. Even though vegetable oil is used as alternate for diesel fuel, it gives problems like injector cocking with trumpet formation, more carbon deposits and piston oil ring sticking, as well as thickening and gelling of the engine lubricating oil. To overcome these constraints, the processes like pyrolysis, microemulsification, transesterification were especially developed [6-8]. Many studies have been devoted to the development of vegetable oil based alternate fuels for internal combustion engines. Banapurmath et al., [9] have studied the performance and emission characteristics on a single cylinder compression ignition engine with 3 different biodiesel (methyl esters of honge, jatropha and sesame) and reported that all the fuels gave a slightly lower efficiency. HC and CO emissions were slightly higher and NOx emission decreased by about 10%. They have reported that these oils can be used without any major engine modifications. Pryor et al., [10] investigated the performance of compression ignition engine using neat soybean vegetable oil. They reported that the short term test with soybean oil indicated a performance similar to that of diesel fuel and the long term engine testing could not be carried out due to problems such as power loss and carbon build-up on the fuel injectors. Deepanraj et al., [11-13] evaluated the performance and emission characteristics of a single cylinder direct injection diesel engine with palm oil biodiesel and its blends. They found that the acceptable thermal efficiencies were obtained and the specific fuel consumption and exhaust gas temperatures were higher than the diesel. The exhaust emissions obtained were lesser than diesel. Suresh Kumar et al., [14] have investigated the performance and emission characteristics on a single cylinder diesel engine with pongamia pinnata methyl ester and reported decrease in NOx and HC emissions. A 40% blend (B40) of biodiesel in diesel has been recommended by the authors. The goal of this study was to investigate the performance and emission characteristics of a single cylinder, four stroke, direct injection, compression ignition engine fuelled with mahua oil biodiesel and its blends. EXPERIMENTAL SETUP Tests were carried out in a single cylinder, naturally aspirated, vertical, four stroke, constant speed, water cooled, direct injection diesel engine. The engine was operated at a constant speed of 1500 rpm. The series of tests were carried out to evaluate the performance and emission characteristics using diesel, mahua oil biodiesel and their blends. The exhaust gas temperature of the engine was measured using k-type thermocouples. The schematic view of experimental setup used for this test is shown in Fig 1. Fig 1. Schematic view of experimental setup Mahua oil was purchased from the local market in Chennai, India. Biodiesel was prepared from the mahua oil through two step transesterification process. Diesel was purchased from the local bunk near Sriperumbudur, Tamil Nadu. The fatty acid composition of mahua oil used in this study is given in Table 1. The properties of mahua oil, mahua biodiesel and diesel are given in Table 2.