Sagar Kumar Seminar Report.pdf

A Seminar report ON

ELECTRONIC FUEL INJECTION SYSTEM Submitted By SAGAR KUMAR PARIDA 1601298417

Under the guidance of PROF. SAMIR KUMAR PANDA

Submitted to PROF. SAMIR KUMAR PANDA “BIJU PATTANAIK UNIVERSITY OF TECHNOLOGY” In partial fulfillment of the requirement for the award of the degree of bachelor of Technology (B.Tech)

Department of Mechanical Engineering Gandhi Institute for Technology, GRAMADIHA, GANGAPADA, BHUBANESWAR, ODISHA

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CERTIFIFICATE This is to certify that the seminar on “ELECTRONIC FUEL INJECTION SYSTEM” is a bonafied record of the seminar delivered by “SAGAR KUMAR PARIDA”(Regd. No1601298417) under my supervision and guidance, in partial fulfillment of the requirements for the award of Degree of Bachelor of Technology in Mechanical Engineering from GANDHI INSTITUTE FOR TECHNOLOGY, Bhubaneswar for the year 2019-20.

HOD Department of Mechanical Engineering

Seminar Guide

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Seminar Coordinator

ACKNOWLEDGEMENT

The work presented in this dissertation would not have been possible without the help and support of a large number of people .The author first expresses his heartiest gratitude to his guide PROF. SAMIR KUMAR PANDA, Department of Mechanical Engineering, GANDHI INSTITUTE FOR TECHNOLOGY, Bhubaneswar, Odisha, India for his valuable guidance, help and encouragement in the course of the present work. The successful and timely completion of the work is due to his constant inspiration and constructive critism. I take this opportunity to express my deepest gratitude to PROF. SAMIR KUMAR PANDA, Seminar Coordinator, Department of Mechanical Engineering and also a faculty members of the Department of Mechanical Engineering, GIFT, Bhubaneswar for constant advice, useful discussion, encouragement and support in pursuing the B-tech work. The help and cooperation received from the principal and Dean Academic, GIFT, Bhubaneswar are gratefully acknowledged.

SAGAR KUMAR PARIDA Registration no. - 1601298417 Department of Mechanical Engineering Gandhi Institute For Technology, Bhubaneswar, Odisha.

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CONTENT 1. Abstract

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2.Introduction

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3.Basic EFI Principle

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4.Fuel Injection

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5.Types of Fuel Injection

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6.working of Fuel Injection System

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7.Advantages

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8. Disadvantages

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9. Conclusion

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10.Reference

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1. ABSTRACT

In the Modern world, automotive electronics play an important role in the manufacturing of any passenger car. Automotive electronics consists of advanced sensors, control units, and “mechatronic actuator” making it increasingly complex, networked vehicle systems. Electronic fuel injection (EFI) is the most common example of automotive electronics application in Powertrain. An EFI system is basically developed for the control of injection timing and fuel quantity for better fuel efficiency and power output. In this paper, we will explain various types of fuel injection system that are used most commonly now a days and will also explain the various parameters considered during calculating base fuel quantity during runtime.

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2. INTRODUCTION:In modern world electronic controls are use almost in every major domain of automobile. Therefore, the number of ECUs in a vehicle have increased abruptly as compared to the last 10 years. One of the major advantages of using Electronics for controlling fuel injection is precise control and timing of injector which leads to increase in the performance of the engine. Modern electronics has reached that level of advancement that it can precisely perform its functions whilst ensuring better efficiency and performance. They are extremely reliable and required very less maintainace Engine management system (EMS) is an essential part of any vehicle, which controls and monitors the engine. Although many other functions are also catered by EMS but usually it is a custom built computer which is responsible for the running of an engine by monitoring the engine RPM, load and temperature and initiating the ignition at the right time for the prevailing conditions and controlling the flow of fuel to the engine in the exact quantity as required. Embedded controllers are used for the implementation of engine management systems known as Engine control unit (ECU). There is the inability of humans to detect carbon monoxide (CO) by smell/taste and the cumulative effects of CO on the body/blood could lead to carbon monoxide poisoning. Tests are to be carried out in a ventilated area and the use of appropriate gas extraction equipment which is in good working order pressurized fuel can be sprayed out when components are being removed or replaced, this could lead to injury to eyes, face etc. also fire. Potential hazards associated with fire-damaged flour elastomer fuel hose (e.g. ‘Viton®’ fuel hose). Instruction is given on the correct and safe method for removing and replacing components also the correct use and type of fire extinguisher. Coming in contact with engine components e.g. exhaust related parts e.g. catalytic converter when the engine is at working temperature could lead to serious burns .Instruction is given to insure that all guards are in place before starting engine and appropriate personal protective equipment(PPE) worn e.g. overalls, safety boots etc. Improper storage, leaks and spillage of fuel could lead to fire due to sparks ignition sources (including static electricity and mobile phones) Instruction is given on the correct and safe 6

storage of fuel (use of correct container etc.) leaks repaired and mopped as soon as they occur and disposed in an environmental friendly manner. Safety precautions need also be applied to prevent damage to the catalytic converter as un-burnt fuel will damage the unit. Fluor elastomers Explained Fluor elastomers are a class of synthetic rubber which provides Extra ordinary levels of resistance to chemicals, oil and heat, while providing useful service life above 200°C. The outstanding heat stability and excellent oil resistance of these materials are due to the high ratio of fluorine to hydrogen.

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3. Basic EFI Principles Because of the need to comply with exhaust emission regulations, the modern petrol engine requires a fuel system of extreme accuracy and long-term reliability. A correctly matched air fuel ratio must be available at all times, and under all conditions. This is satisfactorily achieved by electronic fuel injection. EFI is a pressurized, indirectinjection system, which uses solenoid operated injectors with a fixed orifice. When they are energized, fuel passes through the injector body. This arrangement is called a multi-point system. One injector is located in each intake manifold runner, or pipe, adjacent to each cylinder. An electronic control unit, or ECU, opens the injectors by pulsing the electrical current. They spray fuel into each intake port, directly in front of each intake valve. Fuel leaving the nozzle is atomized, and it mixes with the air also entering the system, to form a combustible mixture. Fuel pressure is kept at a constant value above manifold pressure, so the amount of fuel injected is determined only by the length of time the injector is held open by the ECU. This is called the pulse width of the injector . The triggering signal to operate the injectors can be supplied from the ignition system, or from crank angle sensors on the crank shaft, or the camshaft. Engine fuel requirements change according to engine speed, load, and temperature, so the ECU needs information on these changes . Sensors measure these variables, and then relay the information to the ECU in the form of electrical signals. The ECU then calculates the duration of pulses necessary to provide the fuel required. Extra fuel required during cold starting can be supplied by increasing the number of injection pulses, or by fitting a separate cold start injector that operates independently of the main injectors, when the engine is cranking. The throttle-body injection system, also called a Central Fuel Injection system, has a single injector, or in some cases, 2 injectors, mounted in a carburettor-like throttle-body. The throttle-body assembly is fitted to the flange of the intake manifold, and the fuel is sprayed into the intake air entering the manifold. The air mixture is then carried through the manifold into the engine. Fuel pressure is maintained at a constant value, and an ECU pulses the injector, or injectors.

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4. FUEL INJECTION Fuel injection is the process of injecting fuel with the air to provide an air-fuel mixture to the engine.This supply has to be precisely controlled and accurately timed to ensure an optimum performance of engine with maximum possible efficiency.

An internal combustion engine, the fuel injection systems is that which delivers fuel or a fuel air mixture to the cylinders by means of a pressure from a pump. Fuel injection means metering fuel into an internal combustion engine. It was originally used in diesel engines because of diesel fuel’s greater viscosity and the need to overcome the high pressure of the compressed air in the cylinders. A diesel fuel injector sprays an intermittent, timed, metered quantity of fuel into a cylinder, distributing the fuel throughout the air within. Fuel injection is also now used in gasoline engines in place of a carburetor. In gasoline engines, the fuel is first mixed with air, and the resulting mixture is delivered to the cylinders. Metering of the fuel charge may be performed mechanically or electronically. In a diesel engine, the fuel injected directly into the combustion chamber (direct injection) or into a smaller connected auxiliary chamber (indirect injection). In the spark-ignition engine, the fuel is injected into the before it enters the combustion chamber by spraying the fuel into the air stream passing through the throttle body (Throttle Body Injection) or into the air flowing through the port to the intake valve. On automotive spark ignition engines, the carburetor has largely been replaced by a gasoline fuel injection system with either mechanical or electronic control of fuel metering.

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5. TYPES OF FUEL INJECTION We enjoy fuel injection in almost every modern vehicle. But not all fuel injection systems are created equally, and some are vastly superior to others There are four types of fuel injection systems are used for different types of Engine , these are describe in below a) Throttle body fuel injection, or TBFI b) Multiport injection c) Sequential injection d) Direct injection

5.1 Throttle body fuel injection, or TBFI Also referred to as single port, this was the earliest type of fuel injection to hit the market. All vehicles have an air intake manifold where clean air first enters the engine. TBFI works by adding the correct amount of fuel to the air before it is distributed to the individual cylinders. The advantage of TBFI is that it’s inexpensive and easy to maintain. If you ever have an issue with your injector, you’ve only got one to replace. Additionally, since this injector has a fairly high flow rate, it’s not as easy to clog up. Technically, throttle body systems are very robust and require less maintenance. That being said, throttle body injection is rarely used today. The vehicles that still use it are old enough that maintenance will be more of an issue than it would with a newer, lower mileage car.

Fig.1 Throttle body Fuel Injection

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5.2 Multiport Injection; Multiport injection simply moved the injectors further down towards the cylinders. Clean air enters the primary manifold and is directed out towards each cylinder. The injector is located at the end of this port, right before it’s sucked through the valve and into your cylinder. The advantage of this system is that fuel is distributed more accurately, with each cylinder receiving its own spray of fuel. Each injector is smaller and more accurate, offering an improvement in fuel economy. The downside is that all injectors spray at the same time, while the cylinders fire one after the other. This means that you may have leftover fuel in between intake periods, or you may have a cylinder fire before the injector has had a chance to deliver additional fuel. Multiport systems work great when you are traveling at a consistent speed. But when you are quickly accelerating or removing your foot from the throttle, this design reduces either fuel economy or performance.

Fig 2 .Multi Port Injection System

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5.3 Sequential Injection Sequential fuel delivery systems are very similar to multiport systems. That being said, there is one key difference. Sequential fuel delivery is times. Instead of all injectors firing at the same time, they deliver fuel one after the other. The timing is matched to your cylinders, allowing the engine to mix the fuel right before the valve opens to suck it in. This design allows for improved fuel economy and performance. Because fuel only remains in the port for a short amount of time, sequential injectors tend to last longer and remain cleaner than other systems. Because of these advantages, sequential systems are the most common type of fuel injection in vehicles today. The one small downside to this platform is that it leaves less room for error. The fuel / air mixture is sucked into the cylinder only moments after the injector opens. If it is dirty, clogged, or unresponsive, your engine will be starved of fuel. Injectors need to be kept at their peak performance, or your vehicle will start to run rough.

5.4 Direct Injection If you’ve started to notice the pattern, you can probably guess what direct injection is. In this system, fuel is squirted right into the cylinder, bypassing the air intake altogether. Premium automobile manufacturers like Audi and BMW would have you believe that direct injection is the latest and greatest. With regards to the performance of gasoline vehicles, they’re absolutely right! But this technology is far from new. It’s been used in aircraft engines since the second world war, and diesel vehicles are almost all direct injection because the fuel is so much thicker and heavier.

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6. Working of Electronic Fuel Injection System The electronic fuel injection system is a new innovation, this system incorporates electronic computerize to get the best fuel and air comparisons under all engine conditions.

The EFI system basically has the same diagrams as conventional fuel systems. However, the EFI system does not equip with carburetor. Instead, the injector will be placed in front of the intake valve in each cylinders . The EFI system is divided into three: basic subsystems. 1. Fuel Delivery System. 2. Air Induction System 3. Electronic Control System

6.1 Fuel Delivery System It consists of fuel tank, fuel pump, fuel filter, fuel delivery pipe, fuel injector, fuel pressure regulator & fuel return pipe. Fuel is delivered from tank to the injector by electric fuel pump and the Contaminant elements which are present in fuel are filtered out by a high capacity fuel filter. Fuel is maintained at constant pressure by means of a fuel pressure regulator and the undelivered fuel returns to tank through a fuel return pipe.

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6.2 Air Induction System It consists of air cleaner, air flow meter, throttle valve, air intake chamber, intake manifold runner & intake valve. When throttle valve is opened air flows through air cleaner, through air flow meter to and through a intake manifold runner to the intake valve. Air delivered to the engine depends on throttle valve opening.

Air Cleaner

Fuel Delivery pipe

Fuel Return pipe

Fuel tank

Fig.3 Electronic Fuel Injection Overview

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6.3 Electronic Control System Electronic control system is main part of EFI system , the total control of the fuel injecting process is controlled by EFI circuit . For EFI circuit, might be more complicated. However, we will explain a basic of EFI system schematic with a very simple circuit. This circuit consists of three main components they’re

a) Sensor b) ECU (Electronic controlled unit) c) Actuator The sensor will be an indicator or benchmark of the ECU in computing, while the actuator is used as the executor of the result of the ECU calculation (e.g. injector and fuel pump).

Fig.4 Electronic Fuel Injection 15

Typical sensors used in the electronic fuel injection (EFI) system 1. 2. 3. 4. 5. 6.

Intake Air temperature sensor Mass air flow sensor Throttle position sensor Crank shaft position sensor Cam shaft position sensor O2 Sensor

IAT and MAF sensors, will detect air temperature and the mass of air that flowing passing the filter. This will be an early indicator to determine how much gasoline is needed. The TP sensor will detect the opening angle of the throttle valve, it will know the RPM desired by the driver (the higher the RPM the more gasoline it will take) CKP and CMP sensors will give the info to determine when the injector is open, this will make the gasoline spray out fitting during the intake step. O2 sensor, served as feedback or correction of the combustion results, whether the combustion works perfect or premature. Data from O2 sensor, will be used to improve AFM (air fuel mixture). This sensors, locate inside the exhaust manifold.

The data from the above sensors, will form a voltage with a certain value. Each voltage value, has different information to what is measured. The ECU will translate all these voltage values, and perform the calculations. The results, is also in the form of voltage. There are two outputs from the ECU, first ECU output to the injector and second to the fuel pump. The output voltage from the ECU to the injector has a duration, the duration will affect the amount of gasoline sprayed. While the ECU output to the fuel pump, has a value variation. The greater the voltage the greater the pressure generated by the pump, this makes the amount of gasoline coming out of the injector more and more.

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7. Advantages Better atomization and vaporization results in less knocking. 2. Formation of ice at throttle plate is eliminated. 3. Distribution of fuel is independent of vaporization Improvement of volumetric efficiency of the engine 4. Manifold wetting is eliminated due to direct fuel injection into the cylinder 5. Atomization of fuel is independent of cranking speed, hence good atomization even at low speed. 6. Low volatile fuels can also be used. 7. Variation of air fuel ratio is almost negligible, which results in good in Engine performance. 8. Position of injection unit is not so critical, hereby height of engine can be less. 1.

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8. Disadvantages 1. 2. 3.

High maintenance cost. Difficulty in servicing. Possibility of malfunction of some sensors.

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9 . CONCLISION  An electronic fuel injection system has been developed for the diesel locomotives. This involved design and development of suitable interfaces between the ECU of the EFI, test bed controller and the locomotive traction control computer. Mapping of the engine and determination of optimum fuel injection quantities and start of fuel delivery was done.  A reduction in BSFC of 4% has been achieved by the EFI and a significant reduction in smoke opacity levels has also been obtained. 

Reasons for the improvement in the brake specific fuel consumption and the reduction in the smoke capacity levels were further investigated by studying the fuel line pressure, needle lift, in-cylinder pressure and the heat release rates in comparison to the mechanical fuel injection system.

 EFI has been able to optimize the SOP according to different speeds and loads. Lower in cylinder peak pressures are obtained with EFI as compared to the mechanical fuel injection system except at higher engine notches.  At higher engine notches, (namely 7th and 8th engine notch), SOP had to be advanced due to smaller plunger diameter of the EFI pump (as compared to the mechanical FI) in order to deliver required quantity of fuel and to reduce THC emissions and exhaust gas temperatures due to after-burning.  A higher plunger diameter with a shorter fuel injection pulse will be helpful in retarding the injection timing at 7th and 8th notch and reducing the peak cylinder pressures. A 1-D mathematical model of the engine has been developed and the effect of MEIP and the fuel cam rate has been studied.  A higher plunger diameter EFI pump with a higher fuel cam rate is expected to optimize performance and emissions at higher engine notches.

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10.REFERENCE [1] . WILLIAM, H, CROUSE, 1983, Automotive Mechanics (Tata-McGraw Hill Publishing House, New Delhi) [2]4.https://www.researchgate.net/publication/257925421_Development_of_an _Electronic_Fuel_Injection_System_for_a_4Stroke_Locomotive_Diesel_Engine [3]Nakai Hiroaki, Konishi Yukio, Fukushima Akira, ‘An electronically controlled fuel injection system for new diesel engines’, JSAE Review 18, 5782, 1997. [4] Bosch India presentation on Electronic Fuel Injection system for diesel locomotives, 2011 [5] https://clubtechnical.com/electronic-fuel-injection-system

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