Essay: Internal Combustion Engine

Chapter 1 INTRODUCTION
1.1 Introduction: History and Development
Internal Combustion Engine remains the most dominant method of world transportation since its invention in early 19th Century. Extensive research and technology development by engine manufacturers concentrate on two main methods available to improve engine thermal efficiency: one is to improve cylinder indicated efficiency by optimizing the combustion process, and the other is to recover waste heat energy of the engine. Implementation of supercharged/turbocharged combustion engines for automotive output power increasing, combustion efficiency improvement, fuel consumption diminishing, better inlet valve and cylinder cooling, and ecological indicating parameters improvements.
The history of turbocharging is almost as old as that of the internal combustion engine. As early as 1885 and 1896, Gottlieb Daimler and Rudolf Diesel investigated increasing the power output and reducing the fuel consumption of their engines by precompressing the combustion air. In 1925, the Swiss engineer Alfred Büchi was the first to be successful with exhaust gas turbocharging, and achieved a power increase of more than 40 %. This was the beginning of the gradual introduction of turbocharging into the automotive industry.
The first turbocharger applications were limited to very large engines, e.g. marine engines. In the automotive engine industry, turbocharging started with truck engines. In 1938, the first turbocharged engine for trucks was built by the “Swiss Machine Works Saurer”.The Chevrolet Corvair Monza and the Oldsmobile Jetfire were the first turbo -powered passenger cars, and made their debut on the US market in 1962/63. Despite maximum technical outlay, however, their poor reliability caused them to disappear quickly from the market. After the first oil crisis in 1973, turbocharging became more acceptable in commercial diesel applications. Until then, the high investment costs of turbocharging were offset only by fuel cost savings, which were minimal. Increasingly stringent emission regulations in the late 80’s resulted in an increase in the number of turbocharged truck engines, so that today, virtually every truck engine is turbocharged.
In the 70’s, with the turbocharger’s entry into motor sports, especially into Formula I racing, the turbocharged passenger car engine became very popular. The word “turbo” became quite fashionable. At that time, almost every automobile manufacturer offered at least one top model equipped with a turbocharged petrol engine. However, this phenomenon disappeared after a few years because although the turbocharged petrol engine was more powerful, it was not economical. Furthermore, the “turbo-lag”, the delayed response of the turbochargers, was at that time still relatively large and not accepted by most customers.
The real breakthrough in passenger car turbocharging was achieved in 1978 with the introduction of the first turbocharged diesel engine passenger car in the Mercedes-Benz 300 SD, followed by the VW Golf Turbodiesel in 1981. By means of the turbocharger, the diesel engine passenger
Car’s efficiency could be increased, with almost petrol engine “driveability”, and the emissions significantly reduced.
Today, the turbocharging of petrol engines is no longer primarily seen from the performance perspective, but is rather viewed as a means of reducing fuel consumption and, consequently, environmental pollution on account of lower carbon dioxide (CO2) emissions. Currently, the primary reason for turbocharging is the use of the exhaust gas energy to reduce fuel consumption and emissions.
The exhaust from cylinder discharge into a common manifold at pressure higher than the atmospheric pressure. The exhaust gases from all the cylinder expand in exhaust valves to an approximately constant pressure in the common manifold and pass from here to the turbine. Thus the blow-down energy, in the form of internal energy, is converted into work in turbine. The recovery of blow down energy is higher if the pressure ratio of turbine is high. The exhaust gases are maintained at constant pressure during the whole of cycle so that a pure reaction turbine can be used.
1.2 turbocharging
Turbo-charging, simply, is a method of increasing the output of the engine without increasing its size. The basic principle was simple and was already being used in big diesel engines. In turbocharging, the turbocharger is being driven by a gas turbine using the energy in exhaust gases. The major parts of turbocharger are turbine wheel, turbine housing, turbo shaft, comp. wheel, comp. housing & bearing housing.
1.3 Turbocharger
A turbocharger consists of a turbine and a compressor on a shared shaft. The turbine converts heat to rotational force, which is in turn used to drive the compressor. The compressor draws in ambient air and pumps it in to the intake manifold at increased pressure, resulting in a greater mass of air entering the cylinders on each intake stroke. The output of the engine exhaust gas is given to the input of the turbine blades, so that the pressurized air produced. This power, the alternate power must be much more convenient in availability and usage. This increase pressure allows for an air charge with a greater density. The result is increased torque and horsepower. The turbine and the compressor can rotate at speeds of up to 200,000 rpm and the exhaust inlet temperature can reach max temperatures of up to 1050ºC.
1.4 Types of Turbocharger
1.4.1 Single-Turbo
Single turbochargers alone have limitless variability. Differing the compressor wheel size and turbine will lead to completely different torque characteristics. Large turbos will bring on high top-end power, but smaller turbos will provide better low-end grunt as they spool faster. There are also ball bearing and journal bearing single turbos. Ball bearings provide less friction for the compressor and turbine to spin on, thus are faster to spool. Advantage of this type of turbocharger is Simple, generally the easiest of the turbocharging options to install.
1.4.2Twin-Turbo
Just like single turbochargers, there are plenty of options when using two turbochargers. You could have a single turbocharger for each cylinder bank (V6, V8, etc). Alternatively, a single turbocharger could be used for low RPM and bypass to a larger turbocharger for high RPM (I4, I6, etc.). You could even have two similarly sized turbo where one is used at low RPM and both are used at higher RPM. On the BMW X5 M and X6 M, twin-scroll turbo are used, one on each side of the V8.
1.4.3 Variable Geometry Turbocharger (VGT)
Variable-geometry or variable-nozzle turbochargers use moveable vanes to adjust the air-flow to the turbine, imitating a turbocharger of the optimal size throughout the power curve. The vanes are placed just in front of the turbine like a set of slightly overlapping walls. Their angle is adjusted by an actuator to block or increase air flow to the turbine. This variability maintains a comparable exhaust velocity and back pressure throughout the engine’s rev range. The result is that the turbocharger improves fuel efficiency without a noticeable level of turbocharger lag.
1.4.4Electric Turbochargers
An electricsupercharger is a specific type of supercharger that uses an electrically powered forced-air system that contains an electric motor to pressurize the intake air. By pressurizing the air available to the engine intake system, the air becomes more dense, and is matched with more fuel, producing the increased horsepower to the wheels.
1.5 Objective of the Study
• Analysis on effect of engine when turbocharger is attached.
• Analysis the emission and fuel consumption while using turbocharger.
• To improve performance of engine.
Chapter 2 LITERATURE REVIEW
Survey:
1. Increasing the Efficiency of an Engine by the use of Variable Geometry Turbochargers; Srinivasan.C, M.S.Sayooj [1]. Here we studied that, Due to volumetric efficiency limit, use of variable geometrical turbocharger uses of exhaust energy to drive the turbine, which inturn drive the compressor. Compressor drives and increases the volumetric efficiency & increase expansion ratio, power output, torque.
2. Waste Heat Recovery Technologies In Turbocharged Automotive Engine – A Review Alias Mohd Noor, Rosnizam Che Puteh and Srithar Rajoo[2] :Here in this paper heat energy recovery have been identified in the automotive sector, therefore objective is access to each heat recovery technology based on current development research trends & future automotive application. Study the potential energy recoveries, performance of each technology and other factor affecting the implementation.
3. EFFECT OF INTERCOOLER ON TURBOCHARGED DIESEL ENGINE PERFORMANCE; Dr. Sc. Naser B. Lajqi, Dr. Sc. Bashkim I. Baxhaku Mr. sc. Shpetim B. Lajqi[3]. Here we studied that reduce the fuel consumption, method is to reduce the volume cylinder volume of internal combustion engine and result power to be same or higher. Increased air pressure outlet compressor can result in an excessively hot intake charge, significantly reducing the performance gains of turbo charging due to decreased density. Intercoolers have a key role in controlling the cylinder combustion temperature in a turbocharged engine.
4. ELECTRICAL DRIVE FOR COMPRESSOR ON TURBOCHARGED ENGINE, Jaroslav Novak1, Zdenek Cerovsky [4]. Here these paper deals with the torque control of high speed permanent magnet synchronous motor for driving compressor of supercharged combustion engines. Describe their test is place and presents test results achieved on 40 000 rev/min synchronous permanent magnet motor.
5. Study of turbocharged diesel engine operation, pollutant emissions and combustion noise radiation during starting with bio-diesel or n-butanol diesel fuel blends; C.D. E.G. Giakoumis, D.C. Rakopoulos[5]. Here we studied Control of transient emissions from turbocharged diesel engines is an important objective for automotive manufacturers, as stringent criteria for exhaust emissions must be met. Turbocharged diesel engine in order to investigate the formation mechanisms of nitric oxide (NO), smoke, and combustion noise radiation during hot starting for various alternative fuel blends. To this aim, a fully instrumented test bed was set up, using ultra- fast response analyzers capable of capturing the instantaneous development of emissions as well as various other key engine and turbocharger parameters.
6. Novel Configuration for Air Flow Rationalization and Turbo Lag Reduction in CRDI Engine; Shekaina, Dr. T. Jayasingh [6].Power output of a CRDI engine cycle depends on the oxidation of diesel inside the cylinder. As air-fuel ratio should be maintained within tight limits; the amount of air available inside the cylinder determines the maximum power output at a particular cycle. During acceleration mode and particularly during turbo lag periods, the quantity of air available in conventional CRDI engines is not sufficient to meet the desired torque demand. Overcome the problems during acceleration and deceleration; novel concept and control strategies are presented in this paper.
7. Improved Controller Design for Turbocharged Diesel Engine, Magdi S. Mahmoud [7].Turbocharged diesel engine (TDE) equipped with variable geometry turbocharger and exchange gas recirculation is explained in detail. A linear turbocharged diesel engine model is presented and its control techniques are explained in detail. Controllers are designed using the linear-quadratic regulator (LQR), linear-quadratic Gaussian regulator (LQGR), H2, H∞, and mixed H2/H∞.
Review:
1. The function of the turbine is to scavenge waste exhaust heat and translate it into rotational motion. Using a turbocharger also makes an engine eco-friendlier. A second ecological advantage is that it enables the use of a smaller and more efficient engine delivering the same level of performance, which makes for a lighter vehicle and thus further reduces fuel consumption. A turbocharger consists of two fundamental components, a turbine and a compressor. The purpose behind the turbocharger is to overcome the fundamental drawback of the internal combustion engine, its volumetric efficiency limit. The turbines driving turbochargers are characterized by two chief parameters: A/R ratio and turbine radius. Turbochargers are designed such that the A/R ratio is always a constant: as the exhaust gases are directed closer towards the turbine wheel, the area the gas flows through gets smaller. Using traditional turbochargers, an engine designer would have to balance desire for high exhaust flow to drive the compressor against low back-pressure in the exhaust system, which robs the engine of efficiency, and in extreme cases, significantly reduces the amount of power that can be gained from an engine.
2. This paper presents a short study on different waste heat recovery systems available for application in automotive engines. Utilizing a waste heat recovery technology is becoming an increasingly viable means of reducing fuel costs by increasing the energy output from an internal combustion engines. The content of this paper is basically divided into two main parts which are useful for our project. The first part introduces the waste heat recovery and its utilization. The second part provides the reviews on mechanical turbocompounding. Mechanical turbo-compounding includes a conventional turbocharger which recovers exhaust energy in a turbine to boost the air coming into the engine in a conventional fashion. Downstream of the turbocharger turbine, the exhaust gas goes through a second turbine.
3. One of the most effective strategies is engine downsizing. Downsizing, the use of a smaller capacity engine which operating at high specific engine loads, can be achieved by running with high levels of pressure boosting at full load using a supercharger or turbocharger. High levels of pressure boosting compressing air increase its temperature, which can cause a number of problems. The intercooler, situated between the compressor discharge and the intake manifold, serves to lowering charge air temperature by increase the density. Intercooler is a type of heat exchanger which gives up heat energy in the charge to the ambient air.
4. Implementation of supercharged combustion engines for automotive offers output power increasing, combustion efficiency improvement, fuel consumption diminishing, better inlet valve and cylinder cooling, and ecological indicating parameters improvements. This conception is relatively simple but has several disadvantages. Firstly at low speed the turbine does not produce sufficient power and compressor does not produce sufficient pressure. Next disadvantage of turbine driven compressor is the low dynamic response of
The turbine and compressor at quick fuel supply increase. There are two possible solutions. First – the “electrocharger”, that is the fully electric driven compressor can be used. Second – the hybrid driven charger is possible. This solution means that the charger has both turbine drive and electric drive in cooperation. In practice the hybrid driven charger is more advantageous. The electric part of the charger balances the turbine lack of power and improves the system dynamic.
5. The study of diesel engine operation has primarily focused on its steady- state performance. Very important in terms of combustion stability and emissions, case of diesel engine transient operation is starting. Starting is distinguished as either cold or hot, depending on the respective coolant (and lube oil) temperature, with the former case being of greater importance owing to the lower temperatures involved. In vehicular applications, starting is initiated and supported by the electric starter, whereas in large unit applications (marine, industrial), the use of compressed air is favored. The literature concerning the use of butanol/diesel fuel blends in diesel engines and its effects on their performance and exhaust emissions is very limited, a fact that constitutes another important aspect of the originality of the present work.
6. The system consists of a pre- pressure pump to deliver fuel to the high pressure pump from the fuel tank. The high pressure pump pumps fuel to the common rail, which has a pressure regulator that controls the pressure of the fuel inside the common rail. The common rail is connected to the fuel injectors through high pressure fuel lines and the high pressure fuel is readily available at all instants to the fuel injectors. The required mass of air based on the torque demand can be made to flow in to the combustion chamber. Multiple actuation modes can be combined in the same intake stroke, so as to enhance turbulence and combustion rate at very low speeds. When conditions dictate internal exhaust gas recirculation, it can be made possible. Different valve opening and closing angles can be effected during cold start and warm up periods. During idling conditions with minimum load air entering a few cylinders can be completely blocked. During part load, some cylinders can be completely filled with air so that complete combustion is made possible in selective cylinders. This gives compete degree of freedom for operating the cylinders individually based on the torque demand and or load. During turbo lag conditions as high pressure air is stored in the accumulator; this air can be directed into the inlet manifold by operating the pressure regulator valve using the ECU. So, additional mass of air flows into the cylinders and additional torque is produced.
7. In this paper, the plant to be controlled is a turbocharged passenger car diesel engine equipped with exhaust gas recirculation and a variable geometry turbine as shown in Fig. 1. Turbocharger increases the power density of the engine by forcing air into the cylinders, which allows injection of additional fuel without reaching the smoke limit. The turbine, which is driven by the energy in the exhaust gas, has a variable geometry that allows the adaptation of the turbine efficiency based on the engine operating point. The second feedback path from the exhaust to the intake manifold is diesel engine typically equipped with the VGT and EGR and both introduce feedback loops from exhaust to intake manifold. The recirculated exhaust gas is cooled down in the EGR cooler and its mass flow is controlled via the EGR valve. Both the EGR valve and the VGT are pneumatically actuated and fitted with position sensors. An intercooler reduces the temperature of the compressed air coming from the compressor. In addition to the standard production type sensors, for mass air flow (MAF) and manifold absolute pressure (MAP), the engine is equipped with various temperature and pressure sensors as well as with a turbocharger speed and inline shaft torque sensor. Exhaust gas recirculation (EGR) combined with the variable geometry turbocharging provides an important avenue for NOx emission reduction.
Chapter 3 SETUP & PROCEDURE
The chapter contains detailed of experimental set-up, scheme of instrumentation procedure described as under,
1. Description of experimental setup.
2. Component of experimental setup.
3. Turbocharger arrangement.
4. Engine control switch
5. Experimental procedure.
3.1 Description of Experimental Set-up.
3.1.1Test rig
In this the engine is placed on a stand which is applicable to the engine size and shape. The carburettor is attached through rubber bush which is applicable to the port of the carburettor and engine inlet port. After that an air filter is attached to the carburettor which is to be installed at the inlet port. Burette is attached to the stand of an engine which holds the fuel in it to take a measurement, which is passed to carburettor through pipe. From the engine exhaust port exhaust pipe is to be attached and from half of the exhaust pipe turbocharger is installed, at the turbine inlet of the turbocharger the exhaust air is entering to run the turbine wheel. The compressor wheel and turbine wheel are attached with shaft. From the compressor inlet the atmosphere air is entering into the compressor and then compressed air is flown through compressor discharge to air filter through rubber pipe. In the turbocharger the exhaust air is entering the turbine inlet to run the turbine wheel an after that it removes waste air through turbine discharge. At the turbine discharge the silencer is attached to remove waste air to atmosphere. With engine harness the rpm meter is attached to run the engine at different rpm, switch arrangement is also used to on and off the engine. Blower is used for cooling the engine in a steady condition.
3.1.2 Component of experimental setup
3.1.2.1 Engine
In our project, we are taking Bajaj pulsar 150 DTS-i (150cc) four-stroke petrol engine.Internal combustion engines are those heat engines that burn their fuel inside the engine cylinder. In internal combustion engine the chemical energy stored in their operation. The heat energy is converted in to mechanical energy by the expansion of gases against the piston attached to the crankshaft that can rotat .
3.1.2.2 Turbocharger
In our project we are using Indica (1.4 liter) turbocharger. The turbocharger turbine, which consists of a turbine wheel and turbine housing, converts the engine exhaust gas into mechanical energy to drive the compressor. The gas, which is restricted by the turbine’s flow cross-sectional area, results in a pressure and temperature drop between the inlet and outlet.
3.1.2.3 Air Filter
A particulate air filter is a device composed of fibrous materials which removes solid particulates such as dust, pollen, mould, and bacteria from the air.
3.1.2.4 Carburetor
It is a device that blends air and fuel for an internal combustion engine.
3.1.2.5Silencer
Silencer may refer to:Muffler, a device for reducing the amount of noise emitted by the exhaust of an internal combustion engine, Silencer (DNA), a DNA sequence capable of binding transcription regulation factors termed repressors. Suppressor, a device attached to or part of the barrel of a firearm which reduces the amount of noise and flash.
3.1.2.6 Rpm meter
In our project, we have used rpm meter to take measurement at different rpm of an engine.
3.1.2.7 Stand
All setup are put on the stand.
3.1.2.8 Burette
In our project, we have used 50ml burette for measuring fuel consumption.
3.1.3 Turbocharger arrangement
In our project we have placed turbocharger at exhaust pipe which is installed at the exhaust port of an engine. In turbocharger from the compressor the charged or compressed air is flown to the air filter through rubber pipe which is then entering into the carburettor. From the turbine port the waste air thrown out through silencer.
3.2 Engine control switch
Switch arrangement is done to on and off the engine. On behalf of key we have used a switch because the engine is placed on a stand. The switch controls the ignition system.
3.3 Experimental procedure
The experimental set up involves following steps:
1. The engine is placed on a stand.
2. At the engine inlet port carburettor outlet port is attached through rubber bush which is air-tight with the use of clamp.
3. At the carburettor inlet port the air-filter is attached through clamp.
4. On the stand of an engine the burette is attached, from the discharge port fuel is passed to the carburetor through pipe.
5. RPM meter is used to check the engine rpm.
6. In the engine exhaust port silencer is attached which to be cut to near portion of an engine exhaust port to install turbocharger to the inlet of the turbine.
7. At the compressor discharge the rubber pipe is attached to the air-filter.
8. At the turbine discharge the waste or exhaust air is thrown out through silencer muffler.
Chapter 4 COMPARISON AND RESULT
4.1 COMPARISON
4.1.1 Comparison of fuel consumption
NOTE: ALL READING ARE IN MINUTE.
With the use of turbocharger at 1000 rpm there is more fuel consumption because the compressed air is not generating due to less exhaust gas from the engine which cannot rotate the turbine wheel so there is no compressed air produced in the compressor. After 2000 rpm there is a change in the time the fuel consumption decreases so the efficiency of an engine increases.
4.1.2 COMPARISON OF EMMISSION MEASUREMENT
After installing turbocharger emission of gas is getting reduced so less pollution is done.
Chapter 5 CONCLUSION & FUTURE SCOPE
5.1 Conclusions
After this by installing the turbocharger the efficiency of fuel consumption increasesand emission of exhaust gas reduces. Turbocharger decrease the harmful gas emission.so it is beneficial for environment.it reduce fuel consumption therefore economical.it is apply to small capacity engine but require proper maintenance.
5.2 Future scope
After completing the research work, following future scope has been summarized,
• The same study can be investigated with other available turbocharger.
• This experiment can further extended with electric turbocharger.
• More Improvement can be obtained by installing fuel pump and fuel injector.
REFERENCES
1. Srinivasan.C, M.S.Sayooj, Increasing the Efficiency of an Engine by the use of Variable Geometry Turbochargers;International Journal of Innovative Research in Science, Engineering and Technology.
2. Alias Mohd Noor a*, Rosnizam Che Puteh b and Srithar Rajoo;
3. EFFECT OF INTERCOOLER ON TURBOCHARGED DIESEL ENGINE PERFORMANCE; Dr. sc. Naser B. Lajqi, Dr. sc. Bashkim I. Baxhaku Mr. sc. Shpetim B. Lajq
4. ELECTRICAL DRIVE FOR COMPRESSOR ON TURBOCHARGED ENGINE, jaroslav Novak1 , Zdenek
5. Study of turbocharged diesel engine operation, pollutant emissions and combustion noise radiation during starting with bio-diesel or n-butanol diesel fuel blends; C.D. Rakopoulos, A.M. Dimaratos, E.G. Giakoumis.
6. Novel Configuration for Air Flow Rationalization and Turbo Lag Reduction in CRDI Engine; Shekaina, Dr. T. Jayasingh.
7. Improved Controller Design for Turbocharged Diesel Engine, Magdi S. Mahmoud.