May 28, 2018

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1 Volume 118 No ISSN: (on-line version) url: EXPERIMENTAL STUDY ON THE INFLUENCE OF ENGINE PARAMETERS ON THE PERFORMANCE AND EMISSION CHARACTERISTICS OF A DIESEL ENGINE USING FISH OIL BIODIESEL AS FUEL V. NADANAKUMAR 1, V. SUGENTH 2, N. ALAGUMURTHI 3 1 PG Scholar, 2 Assistant Professor, 3 Professor 1,2 Department of Automobile Engineering, 3 Department of Mechanical Engineering 1,2 Hindustan Institute of Technology and Science, Tamil Nadu, India. 3 Pondicherry Engineering College, Puducherry, India. vnadanak@hindustanuniv.ac.in, sugenth123@gmail.com May 28, 2018 Abstract The depletion of petroleum products has become a threat to humanity, that has compelled to find an alternative fuel. Studies have found that biodiesel is considered as a good alternative for diesel. In this research, biodiesel is prepared from fish oil by transesterification process. The tests have proved that 1

2 pure biodiesel gives lesser performance and emission characteristics. So, B20 blend was selected and tested in the engine. The performance and emission characteristics are found out for biodiesel by changing the injection pressuresand injection timing and compared with the characteristics of diesel. The result showed that the performance is nearer to diesel and the emissions are better than diesel.the maximum BTE was observed to be 29.93% for injection pressure P220 and injection timing 23 btdc. The lowest BSFC was found to be lowest for P220, 23 btdc of about 0.27 kg/kwh. Keywords:Biodiesel, Fish oil, B20, Injection Pressure, Injection Timing. 1 INTRODUCTION The depletion of petroleum products has created interest to identify an alternative fuel source. The reserves of oil and gas is expected to be exhausted in the near future. There is a chance for the depletion of resources even before due to increased consumption. Several studies are being done by the research community to study the feasibilities and to commercialize solar, wind, and geothermal energies. Several researches were also done to convert municipal waste to fuel. European countries have planned to use 5.75% of biofuels by the end of 2010 and 10% by the year 2020 [1]. Biodiesel is an alternative diesel fuel derived from the transesterification of vegetable oils and animal fats with alcohols to obtain the respective fatty acid methyl esters. Biodiesel can be blended with fossil diesel fuel or as a pure biodiesel for the use in a diesel engine. The presence of inherent oxygen content in the biodiesel enhances the combustion and plays a major role in reduction of CO and HC emission[2]. Biodiesel can be used as an alternative topetrol and dieselin order to reduce the emissions. At present biodiesel is being extracted from vegetable oil, used cooking oil and industrial waste oil[3,4]. Many researches were done using fish oil biodiesel and its performance and emission characteristics were studied.godiganur et al. used FOBD in a diesel engine and found that the emissions of carbon monoxide (CO) and hydrocarbons (HC) was reduced 2

3 whereas increase inthe emission of NOx when compared to diesel. More over in the study he found that the combustion and performance were more or less similar to that of diesel [5]. Lin and Li, by the test results from their study proved that FOBD showed good brake thermal efficiency and the emissions of CO, NOx, and smoke were observed as less [6]. The study done by Jayasinghe and Hawboldt proved that fish oil biodiesel can be used in the same diesel engine and combustors and also showed reduction in emissions [7].Behcet, in his experiment, used anchovy fish oil biodiesel and concluded that SFC has increased and there was a significant increase in NOx emission due to the high exhaust gas temperature [8,9]. Ushakov et al. and Stigersshowed that the engineran normally with no operational or maintenance impacts [10,11]. Many studies have showed that the increased injection pressure up to a certain point have improved BTE and SFC and also there was a reduction in emissions. It has been observed that ignition delay is decreased with the increase in injection pressure, as formation of finer fuel droplets at high injection pressures led to higher heat transfer rate and earlier evaporation [12]. Varun Goel concluded that there is a significant reduction in emissions and increase in BTE at higher injection pressures [13]. Whereas, a significant increase in NOx emission was observed by the increase in IP because of the increased HRR [14]. If IP is increased beyond a certain limit, it was observed that BTE got reduced. This may be probably because of the incomplete combustion caused due to the poor entrainment of air with the surrounding fuel particles [15]. Deep et al proved that advancing or retarding both injection pressure and timing reduces BTE. HC and CO were better at original engine configuration [16]. BTE has increased with retardation of injection timing and the combustion and emission characteristics were lower than diesel [17]. Shameer et al reviewed that advancing injection timing enhanced the in-cylinder pressure, peak cylinder pressure, heat release rate and ignition delay due to longer ignition delay, finer atomization, lower in-cylinder temperature and rapid combustion rate. But, retarding the injection timing gave the exact opposite results due to shorter ignition delay, high in-cylinder temperature and slow rate of combustion [18]. From the literature survey, it can be concluded that biodiesel can be a good alternate source for 3

4 further research of alternate fuel and performance, combustion and emission characteristics, can be improved by varying injection pressures and injection timing. 2 MATERIALS & METHODOLOGY 2.1 Extraction of Fish Oil The steps involved in producing fish oil are cooking, pressing, evaporation and separation. Cooking was done to coagulate the protein to liberate bound water and oil. The solid phase in coagulate was separated by separation process, where the coagulate was pressed yielding a solid phase called as press cake. Centrifugation process was done in a decanter to remove the sludge from the press liquor and the oil was separated using centrifuge. Decanters and separators are used to remove the major part of theoil and to separate solids from the press liquid, the liquid left behind is called stick water. Multi effect evaporators are engaged for concentrating the stick water. Two stage drying is carried to dehydrate.finally, the oil is extracted. 2.2 Preparation of Biodiesel In a conical flask, 0.3 wt.% of KOH is mixed with 7:1 methanol and oil molar ratio. The fish oil is taken in a beaker and the mixture of methanol and KOH is added, heated at 60 C for 60 minutes. After heating, the mixture is transferred to a separation flask and kept for 24 hours. The process has turned the oil into esters and glycerol. The by-product glycerol gets settled at the bottom, whereas the fatty acid methyl esters of fish oil floats on the top. Glycerol is separated and the methyl esters are washed with water. Table 1: Fuel Properties Properties Diesel Crude Fish Oil Fish Oil Biodiesel FOBD B20 Kinematic Viscosity 40 C in cst Flash Point in C Fire Point C Gross Calorific Value kj/kg 42,800 36, , ,400 Density in kg/m

5 3 EXPERIMENTAL SETUP Figure 1 shows the schematic diagram of the tested engine setup. Experiments were conducted on a Kirloskar TV1 made, single cylinder, four-stroke, constant speed, direct injection diesel engine coupled with eddy current dynamometer. The specifications are given in Table2. Fuel flow transmitter is provided to measure fuel consumptions. A surge tank is provided to avoid pulsations of the air inlet. Cylinder pressure is measured by the piezo sensor. Crank angle is measured by crank angle encoder. Data acquisition device is used for acquiring data acquisition. AVL DI gas analyzer is used to measure the Carbon Monoxide, Nitrogen Oxides and Hydrocarbon emissions in the exhaust. Figure 1: Schematic diagram of the tested engine setup 3.1 Test Procedure The engine tests were done in fairly ambient conditions. The engine was allowed to run at no load for few minutes to stabilize. The engine was operated fromno-loadcondition to full load using diesel for each load, reading was taken after allowing the engine to run for ten minutes to stabilize. Three sets of readings were taken 5

6 and their average is used for calculation. Further tests were conducted using the fuel, fish oil biodiesel B20 with various injection pressures and injection timings for studies.for injection pressure variation, the pressure setting spring in the injector is adjusted and same is checked using Bosch injector pressure tester as shown in figure 2. Injection timing is varied by adjusting the screw provided for varying the timing of fuel supply the same is shown in the figure 3.The procedure is repeated, three set of readings for each injection pressure and injection timing is taken from no load to full load and their average is used for calculation. Figure 3: Procedure of varying injection pressure in the fuel injector Figure 2: Varying injection timing in the diesel engine Description Make No. of Cylinders Type Rated Speed (rpm) Cubic Capacity (litre) Power Rating (HP) Bore (mm) Stroke (mm) Compression Ratio Type of fuel injection Specifications Kirloskar AVI 1 4 stroke, single acting CI engine (3.7 kw) :1 Direct Injection 6

7 Injection Pressure (bar) 200 Start of injection ( btdc) 23 Cooling Water cooled Table 2: Engine Specifications 4 RESULTS AND DISCUSSION 4.1 Performance Characteristics Brake Thermal Efficiency The figure shows the brake thermal efficiency of diesel and FOBD B20 at various injection pressures versus Brake mean effective pressure. The brake thermal efficiency increases as the load increases. The brake thermal efficiency of FOBD at all the injection pressures is lower than diesel. It may be due to the lower calorific value of FOBD. The brake thermal efficiency of FOBD at 220 bar pressure is higher when compared to FOBD injected at 200 bar and 240 bar. At higher injection pressure the droplet size of the fuel particle may get reduced, results in loss of its momentum. This leads to a reduction in combustion, thereby decrease in brake thermal efficiency at 240 bar.the brake thermal efficiency has improved at 23 btdc and reduced at 21 btdc and 25 btdc. This is because at retarded injection timing the required combustion pressure and temperature were not available for good combustion and at advanced injection timing the fuel was deposited on the walls of the combustion chamber without getting ignited [12] Specific Fuel Consumption The figure shows the effect of injection pressure of FOBD with diesel on specific fuel consumption.it is found that the BSFC of diesel and FOBD at all pressures decrease with increase in brake mean effective pressure. The brake specific fuel consumption of diesel is lower than FOBD at all injection pressures as its calorific value is lesser than diesel. The BSFC at injection pressure 220 bar 7

8 Figure 4: Brake Thermal Efficiency Vs Brake Mean Effective Pressure Figure 5: Brake Thermal Efficiency Vs Brake Mean Effective Pressure is lower when compared to all other injection pressures of FOBD. This may be due to the lesser momentum of fuel particles as the particle size is lower at higher pressures. Since the combustion was better at 23 btdc and brake thermal efficiency was increased at the same timing, SFC was found to be lower at 23 btdc than at retardation. The impact of BTE will affect SFC accordingly [12]. Figure 6: Brake Specific Fuel Figure 7: Brake Specific Fuel Consumption vs Brake Mean Consumption vs Brake Mean Effective Pressure Effective Pressure 4.2 Emission Characteristics Hydrocarbon The emission of unburnt hydrocarbon is shown in the figure. Improper combustion leads to the formation of unburnt hydrocarbons. The formation of UBHC is higher with the injection pressure P240. This may be due to less air entrainment, 8

9 which leads to incomplete combustion. Lower injection pressure leads to higher particle size and lower momentum, which leads to incomplete combustion. At full load, the injection pressure P220 recorded lowest HC emission when compared to other injection pressures. All injection timings show reduced HC emission than diesel, but 23bTDC showed more than other timings. Advancing the injection timing reduced the HC emission since the fuel mixed with more air because of longer ignition delay. Retarding the injection timing produced high heat release, thus enhancing combustion. Hence, HC emission was reduced. Figure 8: Hydrocarbon Emission Vs Brake Mean Effective Pressure Figure 9: Hydrocarbon Emission Vs Brake Mean Effective Pressure Carbon Monoxide The figure shows the variation of carbon monoxide emission of diesel and B20FOBD at various injection pressures. Carbon monoxide is formed due to incomplete combustion of the fuel. At full load condition, the CO emission of diesel and B20 FOBD at all injection pressures are high compared to partial loads as more amount of fuel is injected into the cylinder to maintain a constant speed of the engine. Due to the inherent availability of oxygen in the biodiesel the CO emission at all the injection pressures seems to be lower than that of diesel. The amount of CO content is found to be lower for retarded injection timing due to enhanced combustion reactions because of higher heat release. 9

10 Figure 10: Carbon Monoxide Figure 11: Carbon Monoxide Emission vs Brake Mean Emission vs Brake Mean Effective Pressure Effective Pressure Oxides of Nitrogen The higher in-cylinder temperature is one of the major reason for the formation of NOx. The emission of NOx is higher in B20 FOBD at all injection pressures when compared to diesel. This is due to the presence of oxygen which enhances the combustion. At higher injection pressure, the size of fuel droplet decreases and it evaporates quickly and this enhances faster combustion which in turn increases the in-cylinder temperature. This lead to higher NOx emission at higher injection pressure. NOx increases in all injection timing because heat release rate is higher since more fuel is accumulated before start of combustion. Figure 12: NOx Emission vs Brake Mean Effective Pressure Figure 13: NOx Emission vs Brake Mean Effective Pressure 10

11 5 CONCLUSION From the performance and emission graphs, it can be concluded that: The BTE of biodiesel was lower at all injection pressures than diesel and changing the injection timing did not help in improving BTE of FOBD, but P220 showed the best. The HC emissionwas found to be the lowest for P220 injection pressure and at all injection timings better than diesel. The CO emission was found to be lower at all the injection pressures and injection timings when compared to diesel. The NOx emission was found to be higher for P220 and P240 than diesel, and lower for P200. Also, it was higher for 23 btdc than other timings and diesel. References [1] Ejaz M. Shahid, Younis Jamal (2011). Production of biodiesel: A technical review. Renewable and Sustainable Energy Reviews, [2] Mohammed ELKassaby, Medhat A., et al (2013). Studying the effect of compression ratio on an engine fuelled with waste oil produced biodiesel/diesel fuel, Alexandria Engineering Journal, 52, [3] S. Ananthakumar, S. Jayabal, et al (2016). Investigation of performance, emission and combustion characteristics of variable compression engine fuelled with diesel, waste plastics oil blends, The Brazilian Society of Mechanical Sciences and Engineering. [4] Junheng Liu, Ping Sun, He Huang, Jian Meng, Xiaohua Yao (2017). Experimental investigation on performance, combustion and emission characteristics of a common-rail diesel engine fuelled with polyoxymethylene dimethyl ethersdiesel blends Applied Energy, 202,

12 [5] Godiganur S, Murthy CS, Reddy RP. (2010). Performance and emission characteristics of a Kirloskar HA394 diesel engine operated on fish oil methyl esters, Renewable Energy, 35, [6] Lin CY, Li RJ. (2009), Engine performance and emission characteristics of marine fish oil biodiesel produced from the discarded parts of marine fish, Fuel Process Technology, 90, [7] Jayasinghe P, Hawboldt K. (2012), A review of bio-oils from waste biomass: focus on fish processing waste, Renewable Sustainable Energy, 16, [8] Behcet R. (2011), Performance and emission study of waste anchovy fish biodiesel in a diesel engine, Fuel Process Technology, 92, [9] Behcet R, Yumrutas R, Oktay H. (2014). Effects of fuels produced from fish and cooking oils on performance and emissions of a diesel engine, Energy, 71, [10] Ushakov S, Valland H, Esoy V. (2013). Combustion and emissions characteristics of fish oil fuel in a heavy-duty diesel engine, Energy Conversation Management, 65, [11] Steigers JA (2002). Demonstrating the use of fish oil as fuel in a large stationary diesel engine, Alsk energy Auth, [12] Akash Deep, Sarbjot Singh Sandhu et al (2017). Experimental investigations on the influence of fuel injection timing and pressure on single cylinder C.I. engine fuelled with 20% blend of castor biodiesel in diesel, Fuel, [13] Varun Goel, Naresh Kumar et al. Impact of modified parameters on diesel engine characteristics using biodiesel: A review, Renewable and Sustainable Energy Reviews. [14] S. Imtenan, S.M. Ashrafur Rahman et al (2015). Effect of dynamic injection pressure on performance, emission and combustion characteristics of a compression ignition engine, Renewable and Sustainable Energy Reviews,

13 [15] K. Nanthagopal, B. Ashok et al (2016). Influence of fuel injection pressures on Calophylluminophyllum methyl ester fuelled direct injection diesel engine, Energy Conversion and Management, [16] Akash Deep, Sarbjot Singh Sandhu et al (2017). Experimental investigations on the influence of fuel injection timing and pressure on single cylinder C.I. engine fuelled with 20% blend of castor biodiesel in diesel, Fuel, 210, [17] Sakthivel Gnanasekaran, Saravanan N. et al (2016). Influence of injection timing on performance, emission and combustion characteristics of a DI diesel engine running on fish oil biodiesel, Energy, 116, [18] P. Mohammed Shameer, K. Ramesh (2018). Assessment on the consequences of injection timing and injection pressureon combustion characteristics of sustainable biodiesel fuelled engine, Renewable and Sustainable Energy Reviews, 81,