Effect of Ethanol-Biodiesel-Diesel Blend on Performance and Emission Characteristics of a DI Diesel Engine Sharad P. Jagtap 1* , Anand N. Pawar 2 , Subhash Lahane 3 1 Department of Mechanical Engineering, Jawaharlala Darda Institute of Engineering and Technology, Yavatmal 445001, Maharashtraa, India 2 Maharashtra State Board of Technical Education, Regional Office, Aurangabad 431005, Maharashtra, India 3 Department of Mechanical Engineering, College of Engineering, Pune 411005, Maharashtra, India Corresponding Author Email: jagtapsp@gmail.com https://doi.org/10.18280/ijht.390119 ABSTRACT Received: 2 September 2019 Accepted: 20 December 2020 A significant increase in every nation’s energy demand and insufficient conventional energy reservoirs for long duration, there became necessary requirement to shift from non- renewable to renewable energy sources. Diesel and biodiesel fuels have different thermo physical properties; hence performance and emission output parameters are also different compares with each other. For effective utilization of biodiesel, the characteristics of conventional single cylinder diesel engine with changing load and static speed (1500 rev/min) conditions are evaluated. The baseline diesel, biodiesel - diesel (BD) B08 [8% biodiesel blended with diesel] and ethanol-biodiesel-diesel (EBD) E05B08 [5% ethanol and 8% biodiesel blended with diesel] by v/v ratio are used for experimentation. Brake thermal efficiency (BTE) reduced from 29.14% with diesel to 27.64% with biodiesel and 28.49% with ethanol blends. It is observed that BTE reduced by 1.5% with biodiesel blend and 0.65% only with ethanol blend. The CO, HC and opacity of exhaust gas pollutants are reduced with biodiesel blend fuel and also further reduced with EBD blend. NOx formation with B08 fuel is enhanced to 1967 ppm from 1557 ppm of baseline diesel whereas it is slightly increased to 1734 ppm by E05B08 fuel. Keywords: biodiesel, diesel engine, ethanol-biodiesel- diesel (EBD) blend 1. INTRODUCTION For development of any country, energy is high intensive input. Now a day’s energy demand increases and to satisfy the demand, requires huge investments to meet them. Energy billing expenses are also highly intensive and hence critically efficient utilization is required. Maintaining efficient energy use has been cultured since from first oil shock (year 1973 oil crisis). In today’s scenario energy efficiency became highly essential because of being the most cost-effective and competitive internationally. Energy efficiency also leads to mitigate global climatic change [1]. Recent higher industrial and automobile sector growth leads more fossil fuel consumption rate and hence government of every nation promoting research and development to use environmentally sound new and renewable energy sources. Many researchers have carried out research work on biodiesel application for many years for compression ignition (CI) engines. Biodiesel has most promising renewable and clean alternative fuel stage and can be blended with diesel fuel for little or no modification. It is biodegradable, no-toxic and sulfur, aromatics in biodiesel is also lower [2]. The presence of sulfur and aromatics in diesel fuel result in formation of particulate matter [3]. In trans- esterification process, kinematic viscosity reduces and calorific value increases. Many experimental investigations to evaluates characteristics on conventional engine with various biodiesels namely from, cashew nuts [4], corn oil [5], cottonseed oil [6], peanut oil [7], beef tallow [8], karanja oil [3] and so on have been carried out by researchers. Pollutants from fuel combustion emission causes known or doubted destructive effects on human health and environment. Air pollutants can be sprayed long distances. They chemically react in the atmosphere and forms secondary pollutants like acid rain or ozone. Pollutants like oxides of nitrogen (NOx), Hydrocarbons (HC), carbon monoxide (CO), and particulates are generated by diesel engines. These pollutants deteriorate urban air quality. Diesel and biodiesel fuel have different thermo physical properties hence the combustion characteristics are also different for variable load condition. Biodiesel having low carbon content (10%) and more oxygen (11%) than conventional diesel fuel [9]. Hence, variations in exhaust emission and engine performance have been noticed by researchers. Thermo physical variations in conventional diesel and biodiesel changes net heat release rate characteristics. It reduces CO, HC, and smoke levels pointedly but upturns the NOx contribution [10-12]. Arunkumar et al. [13] have reported that brake specific fuel consumption (BSFC) is increased by 4% and break thermal efficiency (BTE) reduced by 2.2% with B20 composite of castor biodiesel (20% biodiesel + 80% diesel) compares to diesel application. This is because of low calorific value of biodiesel in B20 blend fuels. CO and HC are reduced by 8.6 and 8.1% respectively. Biodiesel has higher bulk modulus than diesel. For B20 fuel blend, the injection timing advances and hence ignition delay is reduced [3]. Further biodiesel fuel having inbuilt dissolved oxygen, leads to early combustion starts and consequently reduced ignition delay found. This shows higher peak pressure during combustion and consequently peak in-cylinder International Journal of Heat and Technology Vol. 39, No. 1, February, 2021, pp. 179-184 Journal homepage: http://iieta.org/journals/ijht 179