Published in A R DIGITECH

Transcription

1 Design and Experimental Investigation of Turbocharger on Performances of Diesel Engine Arunkumar H S 1,, Ravi kumar S Mutalik 2, Krishna Murthy 3, Ganesha A 4 1, 3, 4 Faculty Department of Mechanical and Manufacturing Engineering, Manipal Institute of Technology, Manipal University, Manipal,Karnataka ; E mail: hsa.royalmechanical@gmail.com ; 2 PG student at VTU PG centre,gulbarga. ABSTRACT A typical Diesel engine may harness up to 30% of the energy contained in the fuel supplied to do useful work under optimum conditions but the remaining 70% of the energy is lost in different ways. Increasing the air utilisation permits greater quantities of fuel to be added, and results in a greater potential output. This is achieved by increasing the density of charge, the apparatus used to increase the air density is known as supercharger/ turbocharger. In this investigation 4- stroke single cylinder diesel engine setup is used. A turbocharger is designed for the given setup under tested.experiments were carried out at 15 %, 30%, 45% and 60% utilization of exhaust energy to run the turbine. The results of the experiments are used to plot the different performance curve under different percentage of utilisation of exhaust gases.results of the experiments are comparedturbocharging with without turbocharging the engine. Keywords: Diesel engine, turbocharger, exhaust energy Introduction: Diesel engine is a popular prime mover for transportation, agricultural machinery and industrial applications. A typical engine may harness up to 30% of the energy contained in the fuel supplied to do useful work under optimum conditions but the remaining 70% of this energy is lost in different ways. Increasing the air consumption permits greater quantities of fuel to be added, and results in a greater potential output. The indicated power produced is almost directly proportional to the engine air consumption. This is achieved by increasing the density of charge, the apparatus used to increase the air density is known as supercharger. Superchargers are centrifugal compressors driven by the exhaust gas turbines by utilizing the exhaust energy of the engine then it is called turbocharger. In this investigation 4- stroke single cylinder direct injection diesel engine setup is used. Turbocharger is designed for the given engine setup and experiment is carried out. In this work 15 %, 30%, 45% and 60% of exhaust energy is utilized to run the turbine. Over view of turbocharger: By utilizing the exhaust gas energy of the engine it recovers a substantial part of energy which would otherwise go waste. Thus the turbocharger will not draw upon the engine power. Total heat input to an engine about 27% to 38% goes into the exhaust the exact percentage depends upon the type of the engine and its operating conditions. Utilization of the exhaust gas energy boosts engine power and results in better thermal efficiency and fuel consumption. Literature Review The turbocharger was invented by Swiss engineer Alfred Büchi. His patent for a turbocharger was applied for use in Diesel ships and locomotives with turbochargers began appearing in the 1920s. During the First World War French engineer AugusteRateau fitted turbochargers to Renault engines powering various French fighters with some 1

2 success. In 1918, General Electric engineer Sanford Moss attached a turbocharger to a V12 Liberty aircraft engine. The engine was tested at Pikes Peak in Colorado at 14,000 feet to demonstrate that it could eliminate the power losses usually experienced in internal combustion engines as a result of reduced air pressure and density at high altitude. Turbochargers were first used in production aircraft engines such as the Napier Lioness, in the 1920s before World War II, although they were less common than engine-driven centrifugal superchargers. The primary purpose behind most aircraft-based applications was to increase the altitude at which the airplane could fly, by compensating for the lower atmospheric pressure present at high altitude. Aircraft such as the 190D, B-17 Flying Fortress, and P-47 Thunderbolt all used turbochargers to increase high altitude engine power. 3. Loading Electrical, Resistive loading 4. Rated Power 3.7 Kilowatt 1500rpm 5. Bore and stroke 6. Compression Ratio 7. Cylinder Capacity 85mm*110mm 16.5: cc 8. Dynamometer DC machine with swinging field 9. Cylinder pressure 10. Starting Auto Start 11. Orifice Diameter Piezo sensor, range 2000 psi, Ajay Sensor make 15mm Fig.2: Schematic representation of experimental setup. Material selection and design: Fig 1: Experimental setup Table 1: Engine Specifications 1. Make kirloskar AV-1 2. Type Single Cylinder Diesel engine, PC based. 2

3 Fig 3:Component of the turbo charger. 1. Exhaust gas chamber: this is made out of mild steel plate being cupped to form the container of diameter 150mm for the depth of40mm and centre is bored to the diameter of 27mm to suit the ball bearing housing. A cap is also made for closing the container. It is used from the top side. 2. Pipe for connecting the exhaust gas chamber: This is a mild steel tube being cut and joined between the flange plate and exhaust gas chamber holder. 3. Flange plate for exhaust gas inlet: This is made out of CRCA plate of 1.6mm thick being cut from the plate for the size of 10mmx80mm and then milled on milling machine to make the rectangular size of 90mmx75mm. It is them marked for the centre hole and side holes and bored for the diameter of 25mm and side holes drilled for the diameter of 12mm, 2nos as per the sketch. This is then welded to the pipe connected to the exhaust gas chamber. 4. Exhaust gas turbine blade: this is made out of CRCA plate of 1.6mm thick being cut and bent to the shape to form the turbine blade of width 20mm and cupping from all three sides to leave it open at one side facing the inlet pipe to be able for the gas to plunge within and effect the pushing and force the turbine blade to move away from the inlet pipe effecting the rotation with respect to the centre. There are five numbers of turbine blades are made and mounted on the centre axle which is held on the ball bearings within the chamber. 5. Ball bearing housings: It is made out of mild steel round bar of diameter 35mm being cut for the length of 15mm and then turned on lathe machine to get the diameter as 32mm and then counter bored for the diameter of 27mm for the depth of 8mm and hole size of 12mm and faced from backside to finish 12mm. such two ball bearing housings are made for this project. Fig.4: Component of Turbocharger 6. Impeller blade:this is a readymade turbine blade being moulded which is used here for pumping the fresh air into the engine. 7. Cold air pumping chamber: This is made out of mild steel sheet of 1mm thick made as a container of diameter 125mm for the depth of 35mm. This is drilled for the diameter 12mm at the centre. Ball bearing housings are made and welded on this chamber at the centre to hold the centre axle on which the turbine blade is held. 3

4 8. Cold air pump pipe: This is a standard pipe being cut and joined to this chamber of the length of 215mm with one side threading which is fixed to the control ball valve of which the other end is connected to the hose nipple which can hold the flexible hose pipe which can be connected to the engine. Experimental Procedure: The engine was started using diesel fuel supply, and it is allowed to reach its steady state condition. The experiments were conducted from zero to maximum load condition with diesel operation. Reading such as fuel consumption, load, and torque were noted. The engine was next run by using turbocharger by utilizing 15%, 30%, 45% and 60% exhaust energy with the above conditions. The performance analysis were carried out as before. Results and discussion: As seen from the Fig 5, BTE is improved with increase in load. This was due to reduction in heat loss and increase in power with increase in load. It is observed that when engine operated with turbocharger by utilizing 15%, 30%, 45% & 60% gave the higher BTE at maximum load conditions as well as at some extent to part load condition. The variation of mechanical efficiency with BP is as shown in Fig (6).Mechanical efficiency is improved with increase in load. This was due to reduction in heat loss and increase in power with increase in load. Engine operated with turbocharger by utilizing 45% exhaust energy resulted in the80 % mechanical efficiency at max load. It is observed that this efficiency is the highest when compared with the engine operated without turbocharger [69 %]. This is may be due to better mixing of the air fuel mixture and more even distribution of the charge in the cylinder. Break Thermal Efficiency B.P. in Kw Fig. 5. Graph of B.P v/s Brake Thermal Efficiency. MECH.EFF without TC 15% 30% 45% 60% Without 15% 30% 45% Engine operated with turbocharger by utilizing 45% exhaust energy gave the 38 % BTE at max load. It is observed that this efficiency is the highest one when compared with the engine operated without turbocharger.bte and with turbocharger by utilizing 15%, 30%, & 60% exhaust energy. This is due to better mixing of the air fuel mixture and more even distribution of the charge in the cylinder % BP Fig 6: Graph of B.P v/s Mechanical Efficiency. It is observed that the BSFC was considerably lower when engine operated with turbocharger by utilizing 45% exhaust energy when compared with engine operated without 4

5 turbocharger at maximum load condition. When engine operated with turbocharger by utilizing 45% exhaust energy BSFC obtained was kg/kwhr which is lower than the engine operated without turbocharger (0.571 kg/ kw- hr). This is due to better mixing and utilization of air-fuel mixture w/o When the engine operated with turbocharger by utilizing 45% exhaust energy gives the highest brake thermal efficiency at maximum and part load conditions. It is observed that the BSFC was considerably lower when engine operated with turbochargerdue to better combustion. BP B.S.F.C B.P 1. Variation in performance and emission of the Fig 7: Graph of B.P vs. B.S.F.C engine with variation of compression ratio of the engine can be studied WITHOUT 15% 30% 45% 60% Fig. 8: Comparison of B.P with turbocharger and without turbocharger with different percentage of exhaust gas utilization. References: 15% 30% 45% 60% When the engine operated with turbocharger by utilizing 45% of the exhaust energy gave maximum mechanical efficiency at maximum as well as part load. Future scope: 2. A study of performance and emission of the engine with turbocharger can be carried at different injection pressure and injection timing. Nomenclature: BTE: Brake Thermal Efficiency BSFC: Brake Specific Fuel Consumption TC: Turbo Charger Conclusions: Engine can be operated with turbocharger by utilizing exhaust energy without any modification. When the engine operated with turbocharger by utilizing 45% exhaust energy gives best performance. [1] Turbocharging turbocharging of ic engine: a review mohdmuqeem1, dr. Manoj kumar. Volume 4, Issue 1, January- February (2013), pp IAEME: [2] A. Kusztelan, Y.F. Yao*, D.R. Marchant, Y. Wang (2011), A Review of Novel Turbocharger Concepts for Enhancements in Energy Efficiency, Int. J. of Thermal & Environmental Engineering Volume 2, No. 2 (2011) [3] MohdMuqeem, Turbocharging With Air Conditioner Assisted Intercooler, IOSR Journal of Mechanical and Civil Engineering (IOSRJMCE) ISSN: Volume 5

6 2, Issue 3 (SepOct 2012), PP [4] J. Cheong, SunghwanCh, Changho Kim, Effect of Variable Geometry Turbocharger on HSDI Diesel Engine, Seoul 2000 FISITA World Automotive Congress June 12-15, 2000, Seoul, Korea. [5] C.D. Rakopoulos, E.G. Giakoumis, Availability analysis of a turbocharged DI diesel engine operating under transient load conditions Energy 29 (2004) , [6] Naser B. Lajqi, Bashkim I. Baxhaku and Shpetim B. Lajqi, Effect of Intercooler on Turbocharged Diesel Engine Performance 13th International Research/Expert Conference, Trends in the Development of Machinery and Associated Technology TMT 2009, Hammamet, Tunisia, October Books: [1] I. C. Engine M.L Mathur and Sharma. [2] Automobile Engineering, Kirpalsingh, Vol 1 & 2, [3] I.C. Engine, Edward. F. Obert, Harper International, Edition [4] Engineering Fundamentals Of I. C. Engine, Willard. W. Pulkrabek, [5] I. C. Engine, V. Ganeshan, Tata Mc Graw Hill, 2 nd Edition