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Analysis of the effect of nozzle hole diameter on ci engine performance using

  1. 1. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 70 ANALYSIS OF THE EFFECT OF NOZZLE HOLE DIAMETER ON CI ENGINE PERFORMANCE USING KARANJA OIL-DIESEL BLENDS 1 Mr. Lijo P Varghese, 2 Mr. Rajiv Saxena, 3 Dr. R.R. Lal 1 M.E. [Heat Power & Thermal] Scholar, Department of Mechanical Engg, Lakshmi Narain College of Technology, Bhopal, Madhya Pradesh, India 2 Professor, Department of Mechanical Engg. Lakshmi Narain College of Technology, Bhopal, Madhya Pradesh, India 3 Professor, AISECT University, Raisen, Madhya Pradesh, India3 ABSTRACT An experimental study was carried out to find out the effect of fuel injector nozzle hole diameter on diesel engine performance using Karanja oil- diesel blends. For this experimental setup a 5.97 KW single cylinder, water-cooled, direct injection diesel engine with dynamometer was used for the experimental work. Engine performance parameters such as brake thermal efficiency (BTE), brake specific energy consumption (BSEC) ,brake power (BP), total fuel consumption(TFC) and exhaust gas temperature were calculated. These performance parameters were measured using three different size nozzles. One nozzle with holes of .25 mm, .25 mm and .15 mm, second nozzle with all three holes of .4 mm size, third nozzle with all three holes of .6 mm size. Results indicated that brake thermal efficiency decreased with the increase in nozzle size. Brake power increased with increase in nozzle size but with increasing load, brake power reduced. The brake specific fuel consumption increased with increase in nozzle size, with karanja oil – diesel blends having less brake specific fuel consumption but at peak load and with nozzle size of .6 mm, diesel had the least brake specific fuel consumption. Exhaust gas temperature increased with increase in nozzle size and percentage of karanja oil to diesel. Keywords: diesel, engine performance, karanja oil, nozzle diameter. 1. INTRODUCTION The consumption of diesel is 4-5 times higher than petrol in India. Due to the shortage of petroleum products and its increasing cost, efforts are on to develop alternative fuels especially, to the diesel oil for full or partial replacement. It has been found that the vegetable oils are promising fuels because their properties are similar to that of diesel and are produced easily and renewably from the crops. Vegetable oils have comparable energy density, cetane number, heat of INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING AND TECHNOLOGY (IJMET) ISSN 0976 – 6340 (Print) ISSN 0976 – 6359 (Online) Volume 4, Issue 4, July - August (2013), pp. 70-79 © IAEME: www.iaeme.com/ijmet.asp Journal Impact Factor (2013): 5.7731 (Calculated by GISI) www.jifactor.com IJMET © I A E M E
  2. 2. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 71 vaporization and stoichiometric air–fuel ratio with that of the diesel fuel. None other than Rudolph Diesel, the father of diesel engine, demonstrated the first use of vegetable oil in compression ignition engine in 1910. He used peanut oil as fuel for his experimental engine [1]. Vegetable oils have almost similar energy density, cetane number, heat of vaporization, and stoichiometric air/fuel ratio compared to mineral diesel fuel. However, straight vegetable oils cannot be used directly in engines. Straight vegetable oils or their blends with diesel pose various long-term operational and durability problems in compression ignition engines, e.g. poor fuel atomization, piston ring-sticking, fuel injector coking and deposits, fuel pump failure, and lubricating oil dilution etc.. The properties of vegetable oils responsible for these problems are high viscosity, low volatility, and polyunsaturated character. Several techniques are proposed to reduce the viscosity of vegetable oils such as blending, pyrolysis, micro-emulsion and transesterification etc. Heating and blending of vegetable oils reduce the viscosity but its molecular structure remains unchanged hence polyunsaturated character and low volatility problems exist. It has been reported that transesterification is an effective process to overcome all these problems associated with vegetable oils [2]. There are many vegetable oils which have properties similar to diesel but viscosity is a major factor against their use, they need to be processed before they can be used with diesel, for this nozzle with increased hole sizes were used for testing the performance of CI engine, as processing add to the cost of bio-diesel. If they would be used at normal standard size nozzles, it may lead to the choking of the nozzles. Vegetable oil can be directly mixed with diesel fuel and may be used for running an engine. The blending of vegetable oil with diesel fuel in different proportion were experimented successfully by various researchers. Blend of 20% oil and 80% diesel have shown same results as diesel and also properties of the blend is almost close to diesel. The blend with more than 40% has shown appreciable reduction in flash point due to increase in viscosity. Some researchers suggested for heating of the fuel lines to reduce the viscosity. Although short term tests using neat vegetable oil showed promising results, longer tests led to injector choking, more engine deposits, ring sticking and thickening of the engine lubricant [3]. Micro-emulsification, pyrolysis and transesterification are the remedies used to solve the problems encountered due to high fuel viscosity. Although there are many ways and procedures to convert vegetable oil into a Diesel like fuel, the transesterification process was found to be the most viable oil modification process [2]. The use of vegetable oils, such as palm, soya bean, sunflower, peanut, and olive oil, as alternative fuels for diesel is being promoted in many countries [4]. Y.He et al. [5] conducted tests with blend of 30% cottonseed oil and 70% diesel on diesel engine. The experimental results obtained showed that a mixing ratio of 30% cottonseed oil and 70% diesel oil was practically optimal in ensuring relatively high thermal efficiency of engine, as well as homogeneity and stability of the oil mixture. For this purpose, a modification of diesel engine structure is unnecessary, as has been confirmed by the literature. High viscosity of cottonseed oil is one of the key problems preventing its widespread application. Deshpande [6] used blends of linseed oil and diesel to run the CI engine. Minimum smoke and maximum brake thermal efficiency were reported in this study. Barsic et al. [7] conducted experiments using 100% sunflower oil, 100% peanut oil, 50% of sunflower oil with diesel and 50% of peanut oil with diesel. A comparison of the engine performance was presented. The results showed that there was an increase in power and emissions. In another study, Rosa et al. [8] used sunflower oil to run the engine and it was reported that it performed well. Blends of sunflower oil with diesel and safflower oil with diesel were used by Zeiejerdki et al. [9] for his experimentation. He demonstrated the least square regression procedure to analyze the long-term effect of alternative fuel and I.C. engine performance. The straight karanja oil blend up to 25% with the petro diesel meets the standard specification. However blending of this oil with petro diesel up to 20% (by volume) can be used safely in a conventional CI engine without any engine modification that could help in controlling air pollution. [10]
  3. 3. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July 2. EXPERIMENTAL SETUP AND METHODOLOGY A Kirloskar make, single cylinder, water cooled, direct injection diesel engine was selected for the present research work, which is primarily used for agricultural electricity generations. It is a single cylinder, four str of loading mechanically since it is coupled with mechanical dynamometer. The engine can be hand started using decompression lever. The inlet and exhaust valves are operated by an overhead camshaft driven from the crankshaft. The fuel pump is driven from the end of camshaft. The detailed technical specifications of the engine are given in Table 1. Table No.1: For determining the effect of injector nozzle diameter on diesel engine performance, the size of the nozzle holes were increased using the process of laser drilling. Nozzle is heat treated as a result it cannot be machined using ordinary machining processe and EDM (electric discharge machining). .6 mm sizes and nozzle with holes of .25 mm, .25mm and .15mm. FIGURE NO.1 (N-SPEED SENSOR, W-LOADING ARRANGEMENT, T1 Make TYPE Rated Brake Power(kW) Rated Speed (rpm) Number of Cylinder Bore x Stroke (mm) International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 72 EXPERIMENTAL SETUP AND METHODOLOGY A Kirloskar make, single cylinder, water cooled, direct injection diesel engine was selected for the present research work, which is primarily used for agricultural activities and household electricity generations. It is a single cylinder, four stroke, and water-cooled engine. It has a provision of loading mechanically since it is coupled with mechanical dynamometer. The engine can be hand lever. The inlet and exhaust valves are operated by an overhead camshaft driven from the crankshaft. The fuel pump is driven from the end of camshaft. The detailed technical specifications of the engine are given in Table 1. Table No.1:- Specifications of the Diesel Engine For determining the effect of injector nozzle diameter on diesel engine performance, the size of the nozzle holes were increased using the process of laser drilling. Nozzle is heat treated as a result it cannot be machined using ordinary machining processes. It can be machined by laser drilling electric discharge machining).The tests were conducted on nozzles with holes of .4 mm, .6 mm sizes and nozzle with holes of .25 mm, .25mm and .15mm. FIGURE NO.1 experimental set-up LOADING ARRANGEMENT, T1-T6-TEMPERATURE SENSORS, I INJECTOR) Kirloskar Oil Engines Ltd. single cylinder, 4 stroke, vertical, water-cooled engine 5.968 1800 One 87.5 x 110 International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – August (2013) © IAEME A Kirloskar make, single cylinder, water cooled, direct injection diesel engine was selected activities and household cooled engine. It has a provision of loading mechanically since it is coupled with mechanical dynamometer. The engine can be hand lever. The inlet and exhaust valves are operated by an overhead camshaft driven from the crankshaft. The fuel pump is driven from the end of camshaft. The detailed For determining the effect of injector nozzle diameter on diesel engine performance, the size of the nozzle holes were increased using the process of laser drilling. Nozzle is heat treated as a It can be machined by laser drilling The tests were conducted on nozzles with holes of .4 mm, TEMPERATURE SENSORS, I- cooled engine
  4. 4. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 73 2.1 The Fuel Properties The fuel properties of the karanja oil and its blends are furnished. Table No.2: Fuel properties of Karanja Oil and its Blends 3. PERFORMANCE CHARACTERISTICS 3.1 Brake Specific Fuel Consumption(BSFC) The brake specific fuel consumption of engine was increased with increase in the nozzle size, the brake specific fuel consumption was less when using karanja oil and diesel blends with B20 having the least brake specific fuel consumption but at peak loads, while running on diesel fuel, engine had least specific fuel consumption. Nozzle with hole sizes of .25 mm, .25 mm and .15 mm, had the least brake specific fuel consumption while nozzle with all three holes of .6 mm had the highest brake specific fuel consumption. The comparative brake specific fuel consumption for all the three nozzles at various loads is given in the below figures. FIGURE NO.2 BSFC in kg/kw-hr at 25% load for different nozzle sizes FIGURE NO.3 BSFC in kg/kw-hr at 50% load for different nozzle sizes DIESEL B5 B10 B15 B20 BRAKESPECIFICFUEL CONSUMPTION BRAKE SPECIFIC FUEL CONSUMPTION AT 25% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm Properties Diesel Karanja oil B5 B10 B15 B20 Calorific value, KJ/kg 43500 43119 42738 42357 41956 Specific gravity 0.835 0.837 0.840 0.842 0.844 Kinematic viscosity at 30°C, 2.5 2.78 2.89 3.06 3.64 DIESEL B5 B10 B15 B20 BRAKESPECIFICFUEL CONSUMPTION BRAKE SPECIFIC FUEL CONSUMPTION AT 50% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  5. 5. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 74 Fig.4 BSFC in kg/kw-hr at 75% load for different nozzle sizes Fig.5 BSFC in kg/kw-hr at 100% load for different nozzle sizes 3.2 Brake Power(BP) In general brake power increased with increased in nozzle size, that is a nozzle with all holes of .6 mm produced more brake power compared to the nozzle with all holes of .4 mm, and nozzle with hole sizes of .25 mm, .25 mm and .15 mm. At maximum load condition B20 fuel produced the highest brake power, for nozzles with all holes of .6 mm and .4 mm but nozzle with hole sizes of .25 mm, .25 mm and .15 mm diesel fuel produced the maximum brake power. Fig.6 brake power in kW at 25% load for different nozzle sizes DIESEL B5 B10 B15 B20 BRAKESPECIFICFUEL CONSUMPTION BRAKE SPECIFIC FUEL CONSUMPTION AT 75% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKESPECIFICFUEL CONSUMPTION BRAKE SPECIFIC FUEL CONSUMPTION AT 100% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKEPOWER BRAKE POWER AT 25% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  6. 6. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 75 Fig.7 brake power in kW at 50% load for different nozzle sizes Fig.8 brake power in kW at 75% load for different nozzle sizes Fig.9 brake power in kw at 100% load for different nozzle sizes DIESEL B5 B10 B15 B20 BRAKEPOWER BRAKE POWER AT 50% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKEPOWER BRAKE POWER AT 100% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKEPOWER BRAKE POWER AT 75% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  7. 7. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 76 3.3 Brake Thermal Efficiency(BTE) Brake thermal efficiency decreased with increase in the nozzle sizes. At 25%, 50%, 75% load conditions B20 produced the maximum brake thermal efficiency with some exception. But at peak load condition, for all the three nozzles, diesel fuel produced the maximum break thermal efficiency. Comparative analysis of brake thermal efficiency at various load conditions for different nozzle sizes is given in the below figures. Fig.10 BTE at 25% load for different nozzle sizes Fig.11 BTE at 50% load for different nozzle sizes Fig.12 BTE at 75% load for different nozzle sizes DIESEL B5 B10 B15 B20 BRAKETHERMAL EFFICIENCY BTE AT 25% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKETHERMAL EFFICIEENCY BTE AT 50% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 BRAKETHERMAL EFFICIEENCY BTE AT 75% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  8. 8. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 77 Fig.13 BTE at 100% load for different nozzle sizes 3.4 Total Fuel Consumption(TFC) Total fuel consumption increased with the increase in the nozzle hole sizes. The total fuel consumption was less when engine was running on karanja oil-diesel blends but at peak load, the total fuel consumption was less when diesel fuel was used. Fig.14 TFC in kg/hr at 25% load for different nozzle sizes Fig.15 TFC in kg/hr at 50% load for different nozzle sizes DIESEL B5 B10 B15 B20 BRAKETHERMAL EFFICIEENCY BTE AT 100% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 TOTALFUEL CONSUMPTION TOTAL FUEL CONSUMPTION AT 25% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 TOTALFUEL CONSUMPTION TOTAL FUEL CONSUMPTION AT 50% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  9. 9. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 78 Fig.16 TFC in kg/hr at 75% load for different nozzle sizes Fig.17 TFC in kg/hr at 100% load for different nozzle sizes 4. CONCLUSIONS With increase in the nozzle size brake specific fuel consumption increased which was least for the B20 fuel but at peak load diesel fuel produced the least brake specific fuel consumption. The exhaust gas temperature increased with increase in nozzle size, with increase in karanja oil-diesel blending ratio, exhaust gas temperature increased but B20 produced less exhaust gas temperature compared to B15 for all nozzle sizes. The brake thermal efficiency decreased with increase in nozzle hole size, karanja oil-diesel blends produced more brake thermal efficiency but at peak load diesel fuel produced the maximum brake thermal efficiency for all the nozzle sizes. Brake power increased with the increase in the nozzle size with some exceptions, at peak load B20 produced the highest brake power at .6 mm nozzle size. The total fuel consumption increased with the increase in the nozzle hole size, karanja oil-diesel blends had less total fuel consumption as compared to diesel fuel. But at peak load, diesel fuel had the least total fuel consumption at all nozzle sizes. DIESEL B5 B10 B15 B20 TOTALFUEL CONSUMPTION TOTAL FUEL CONSUMPTION AT 75% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm DIESEL B5 B10 B15 B20 TOTALFUEL CONSUMPTION TOTAL FUEL CONSUMPTION AT 100% LOAD NOZZLE HOLES SIZE .6,.6 &.6 mm NOZZLE HOLES SIZE .4,.4 &.4 mm NOZZLE HOLES SIZE .25,.25 &.15 mm
  10. 10. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 4, Issue 4, July - August (2013) © IAEME 79 5. REFERENCES Journal Papers [1] A.S. Ramadhas, C. Muraleedharan, S. Jayaraj, “Performance and emission evaluation of a diesel engine fuelled with methyl esters of Rubber seed oil” Renewable Energy, 2005. [2] Ayhan Demirbas. Biodiesel fuels from vegetable oils via catalytic and non-catalytic supercritical alcohol transesterification and other methods: a survey Elsevier, Energy Conversion and Management. [3] Nwafor. Emission characteristics of diesel engine running on vegetable oil with elevated fuel inlet temperature, Biomass and Bio energy journal. [4] B.K. Barnwal, M.P. Sharma. Prospects of biodiesel production from vegetable oils in India, Renewable and Sustainable Energy Reviews. [5] Y. He, Y.D. Bao. Study on cottonseed oil as a partial substitute for diesel oil in fuel for single-cylinder diesel engine, Renewable Energy. [6] Deshpande N V. Bio-diesel: An alternative fuel for compression ignition engines, Proceedings on Recent trends in alternative fuels, Nagpur, India, 2002. [7] Barsic NJ, Humke H. Performance and emission characteristics of a naturally aspirated diesel engine with vegetable oil, SAE 810262, 1981. [8] Rosa Radu. The use of sunflower oil in diesel engines, SAE 972979, 1997.Tavel, P. 2007 Modelling and Simulation Design. AK Peters Ltd. [9] Zeiejerdki K, Pratt K. Comparative analysis of the long term performance of a diesel engine on vegetable oil, SAE 860301, 1986. [10] Sudipta Choudhury and Dr. P K Bose, Karanja Oil – Its Potential and Suitability as Biodiesel. [11] Mahesh P. Joshi and Dr. Abhay A. Pawar, “Experimental Study of Performance-Emission Characteristics of Ci Engine Fuelled with Cotton Seed Oil Methyl Ester Biodiesel and Optimization of Engine Operating Parameters”, International Journal of Mechanical Engineering & Technology (IJMET), Volume 4, Issue 1, 2013, pp. 185 - 202, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359. [12] Ramaraju. A and Ashok Kumar T V, “Biodiesel Development from High Free Fatty Acid Marotti Oil”, International Journal of Mechanical Engineering & Technology (IJMET), Volume 1, Issue 1, 2010, pp. 227 - 237, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359. [13] Manu Ravuri, D.Harsha Vardhan, V.Ajay and M.Rajasekharreddy, “Experimental Investigations and Comparison of Di Diesel Engine Working on Jatropha Bio-Diesel and Jatropha Crude Oil”, International Journal of Mechanical Engineering & Technology (IJMET), Volume 4, Issue 3, 2013, pp. 24 - 31, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359. [14] A. P. Patil and H.M.Dange, “Experimental Investigations of Performance Evaluation of Single Cylinder, Four Stroke, Diesel Engine, using Diesel, Blended with Maize Oil”, International Journal of Mechanical Engineering & Technology (IJMET), Volume 3, Issue 2, 2012, pp. 653 - 664, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359. [15] Rajan Kumar, Dr. Manoj K Mishra and Dr. Shyam K Singh, “Performance and Emission Study of Jatropha Biodiesel and its Blends on C.I. Engine”, International Journal of Mechanical Engineering & Technology (IJMET), Volume 4, Issue 3, 2013, pp. 85 - 93, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359.

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