# Gas exchange process for IC-engines: poppet valves, valve timing and variable valve actuation

Size: px
Start display at page:

Download "Gas exchange process for IC-engines: poppet valves, valve timing and variable valve actuation"

Transcription

1 Gas exchange process for IC-engines: poppet valves, valve timing and variable valve actuation Topics Analysis of the main parameters influencing the volumetric efficiency in IC engines: - Valves and valve timing - Dynamic effects - Turbocharging Introduction At the end of each cycle, in an IC engine the burned gases have to be replaced by new charge of air/fuel and (often) recycled exhaust gases. The gas exchange process is quite complex since it involves many time-dependent phenomena, such as: unsteady and compressible flows, frictional losses, heat transfers, area changes and complex geometrical paths. During the gas exchange process, because of the cyclic operation of cylinders, the flows through each component are pulsating and strongly influenced by inertia effects and wave actions, and hence difficult to be analyzed. Layout of the intake and exhaust systems for a 4- stroke, TC, SI engine. Volumetric efficiency or filling coefficient Volumetric efficiency (ηv) or filling coefficient (λv), defined as: ma: trapped air mass per cycle mt: theoretical amount of mass that can fill the cylinder displaced volume ρa: air density at reference conditions V: cylinder displaced volume The filling coefficient measures the engine capability to fill its displacement with air. For this reason, it is defined as the ratio between the trapped air mass per cycle and the theoretical amount of mass that can fill the engine displacement at reference conditions. The actual air mass, ma, aspirated inside the cylinder at the end of the single cycle, is different from the ideal one mt, for different reasons: 1) Burned gases inside the combustion chamber Vc at the end of the exhaust process, have a pressure pr which is higher than the atmospheric pressure pa. Therefore, burned gases expand, at the beginning of the induction stroke, filling part of the displacement Vd (that, instead, should be filled by fresh charge). 2) Pressure inside the cylinder at the end of the induction stroke is lower than pa, because energy must be spent to overcome frictional losses along the induction system and to accelerate the fluid through the inlet ports. The inlet valve does not close at BDC (point 1), but somewhat later at the beginning of the

2 compression stroke (point i), where is pi> pa. However, the available volume Vi for fresh charge is then lower than V1, hence the loss in filling is evident. 3) During the intake exchange process, heat is exchanged between the hot engine walls and the entering fresh fluid, increasing the temperature of the new charge and hence decreasing the air density inside the cylinder at the end of the induction process. 4) The gas exchange process is influenced by dynamic effects, due to unsteady flows and pressure wave actions, which can improve or hinder the cylinder filling, depending on whether the geometry of the induction system is tuned or not with available times. To overcome this limitation, some car engines use now induction systems of variable geometry with the rotational speed. 5) For reasons of simplicity, cost and reliability, the conventional engines are equipped with a fixed angular valve timing. This means that the crank angles of valve opening and closing does not vary with the engine rotational speed n. For this reason, times available for the exchange process decrease when the engine speed increases. Hence fixed timings (with fixed geometry) can be optimized just for a limited engine speed range. A first estimation of the filling coefficient (λv) can be achieved by applying the energy conservation to the intake process: which, after some manipulation, can lead to the following expression: Numerical fluid dynamic models are needed for more accurate predictions. Dependency of the volumetric efficiency from the engine speed: 1) CURVE A: Nondependent speed effects (like fuel vapour pressure) drop ηv below 100% 2) CURVE B: Charge heating in the manifolds and cylinder drops curve A to curve B. It has a greater effect at lower engine speeds, due to the longer gas residence times.

3 3) CURVE C: Frictional flow losses increase as the square of the engine speed, and drop curve B to curve C. 4) CURVE D: At higher engine speeds, the flow into the engine during at least part of the intake process becomes chocked. Once it occurs, further increases in speed do not increase the flow rate significantly, so volumetric efficiency decreases sharply (curve C to curve D). 5) The induction ram effect, at higher engine speeds, raises curve D to curve E. Late inlet valve closing, which allows advantage to be taken of increased charging at higher speeds, results in a decrease of ηvat low engine speeds due to backflow (curves C and D to F). Finally, intake and/or exhaust tuning can increase the volumetric efficiency (often by a substantial amount) over part of the engine speed range, curve F to G. Poppet Valves In a four-stroke engine, the most significant flow restriction, along all the intake and exhaust systems, is usually located in the poppet valves. For this reason, the flow through these engine components has to be analyzed. Modern four-stroke engines usually control the opening and closing of the intake and exhaust ports of the cylinders by poppet valves. They offer: - Minimum fluid-dynamic losses - High sealing ability and good reliability while subjected to high accelerations (and hence inertia forces). The quantity of heat absorbed by the valve when heat is released from the products of combustion amounts roughly to 70% by conduction through the valve head when it is closed, and 30% by conduction through the fillet underside of the valve when it is open and the exhaust gas is escaping through the exhaust port. When the valve is closed, about 76% of the total heat input from the heat released by combustion is transferred by conduction to the cylinder head coolant by way of the valve seat, and only 24 % of the total heat input to the valve is conveyed through the valve stem to the cylinder head coolant via the valve guide.

4 High operating temperatures due to incorrect ignition timing and mixture strength raise the valve head temperature until the valve head becomes the focal point for pre-ignition. A portion of the valve head then becomes the point of ignition which again leads to further heating of the valve head until eventually the valve seat distorts. Consequently, the poor seating of the valve during the combustion phase provides an escape route for some of the burning gases and, as a result, causes excessive local overheat and burning in the valve rim and seat region. If large quantities of combustion products accumulate around the valve seat they will eventually become dislodged due to the repeated valve closing impact, some of the break-away deposits will then provide exit passages for the burning gases. The partial radial tunnelling around the valve seat when it is closed will therefore cause the valve seat to overheat as the gas escapes, since the heat flow path around the head is interrupted. This may result in severe carburization and oxidation of the valve seat surface, and ultimately it may burn a semiconcave groove into and around the valve seat. The name 'guttering' is derived from the top face contour of house guttering. Flow coefficient Flow through a valve is mainly influenced by the available area and the pressure head across cylinder and pipe. The valve flow area (both exhaust and intake) is rapidly varying with time, or better it is a function of crank angle θ, which is proportional to time, for a given shaft rotational speed ω. The pressure upstream the valves changes continuously with time, therefore the flow through the valve results highly unsteady. It is also turbulent, and some useful information can be drawn from flow tests in steady-state conditions. The figure illustrates the main device used in these flow tests. Direct flow (from the manifold to cylinder): through the actual port-valve group (or a preliminary model), air is aspirated by a fan located in the cylinder, to simulate the piston effect. Reverse flow (from the cylinder to the pipe): in this case, the fan is pressuring the cylinder. In both cases, the lift is kept constant and, at steady flow conditions, actual air mass flow rates are measured, for different valve lifts and pressure heads Δpv across the valve.

5 To derive more general information about the flow, that may be extended to other engines operating at similar fluid-dynamic conditions, the measured actual air mass flow rate values are made dimensionless by dividing them by the ideal mass flow rates that would pass through a reference area Avref under the same Δpv in an iso-entropic expansion. This is the valve flow coefficient C: ma = measured air mass flow rate mid = ideal air mass flow rate that would pass through a reference area Avref under the same Δpv in an iso-entropic expansion. Avref = is the reference area, set to be constant and equal to the inner seat area: m* is the critical or sonic mass flow. The flow coefficient for fully turbulent flow is independent on Re. where a01 is the total speed sound in 1 and the compressible flow function is: The flow coefficient includes not only the typical losses of the actual flow (friction, heat exchange, energy dissipation, etc.), but also effects of continuous change in geometric flow area. Since the flow is fully turbulent, the effect of Δpv is negligible, and typical values of C are usually plotted as function of l/dv (non-dimensional valve lift). C is increasing with l/dv since the geometric flow area increases, but it do not reach values near unity because the ideal flow rate is referred to Avref, that is greater than the actual one, even at lmax. C values for reverse flow are lower than for direct flow due to higher energy losses. To avoid complex calculations, it is useful to refer to the following areas, which are simple to be determined: The lateral surface Aca of the cylinder of base diameter dv and height l, called curtain area and expressed by:

6 The area Av of the cross section of the valve seat, or seat area, expressed by: The curtain area is not the minimum flow area, but it varies linearly with lift, including its effect in the change of flow section. It is therefore useful to consider the following ratio Γ: The coefficient Γ reaches unity when is l/dv = 0.25, showing that it is useless to increase the lift beyond the value that makes the curtain area equal to the seat area, because then the seat area (and no more the curtain area) becomes the minimum section of flow control. For this reason, also the flow coefficient reaches the maximum value around l/dv = In each case, it becomes possible to quantitatively assess how much can be gained, in terms of effective flow area, by further increasing the maximum lift, and to compare this advantage with the draw-back of higher accelerations, that are amplified with the ratio of minimum lifts. The flow coefficient increases with l/dv, since the geometric flow area increases, but it does not reach values near unity, because the ideal flow is referred to an area greater than then actual one, even at the maximum lift. The effective geometric flow area is the lateral surface of a cylinder whose diameter is equal to dv and height equal to the valve lift l. The C values are lower for reverse flow than for direct flow, due to higher energy losses, since the poppet valve does not follow the air flow as efficiently as in the direct flow: Port design significantly affects the discharge coefficient performances, which can approach the isolated valve values in case of well designed conditions.

7 Flow Area The motion of a poppet valve is usually designed in order to avoid the oscillations superimposed to the basic lift trend, driven by the cam, and the problems of lubrication and wear. These conditions determine the shape of its acceleration and velocity diagrams. The maximum valve lift is generally the only parameter that can be utilized to improve the cylinder filling. In this optimization process, it is necessary to understand that the minimum flow area is a complex function of lift as well as valve and seat dimensions. The cross-sectional area varies continuously with the valve lift and it is a function of the crank angle θ: h/dv = h/dv(θ) The flow coefficient is function of valve lift: C=C(h/dv) and finally the (instantaneous) effective area is a function of the crank angle. The effective area is the one in correspondence of the vena contracta of the flow. If the flow coefficient is equal to 1 (ideal condition), the effective available cross sectional area for the flow over the reference area will have this slope: Aeff/Aref, where Aref = valve seat area. Flow Coefficient The value of C and the choice of reference area are linked together: their product, C Aref, is the effective flow area of the valve assembly Ae. Several different reference areas have been used, depending on the scope. Valve Diameter The higher the effective flow areas opened by the valves are and the better the filling process is. There is a minimum value of this area, necessary to avoid that the flow reaches the sound velocity a in the minimum restriction. When this happens (the flow becomes chocked during the process) the gas exchange in the cylinder may substantially deteriorates, since fluid velocities can no more increase beyond the sound velocity. Chocking is particularly critical in the intake valve, because it blocks any further raise of mass flow rate, needed to increase the rotational speed of the engine, which then becomes gulped.

8 Filling coefficients, measured on a large set of engines and intake valve designs, correlates quite well with a sort of mean inlet Mach Number, called inlet Mach index or gulp factor Z: Vfmi is an appropriate fluid mean velocity during the inlet process, given by the mean piston speed up, amplified by the ratio between the cylinder cross section Acyl and the seat valve area Av(reduced by the mean flow coefficient during the inlet process, Cmi) A simple model of inlet chocking process allows to correlate the volumetric efficiency with Z by the following relation: The volumetric efficiency is rapidly decreasing after a critical value Zcrit (0.5 according to experiments, 0.75 according to a simplified model), because of choking process in the inlet flow area. The following expression allows to determine the minimum inlet area Av,min, necessary to avoid choking in all the operating range of the engine: The geometry of the combustion chamber limits the area of the valve seats. Examples: flat cylinder head with 2 and 4 valves. They are just theoretical values since the valve seats should be spaced adequately (for strength reasons, insertion of refrigerant passages, placing of spark and/or fuel injector ). The intake valve diameter div is usually larger than the exhaust one dev. Usually, div=1.1 dev. This is because fluid dynamic losses during the intake stroke influences more heavily the filling process. The area available in the cylinder head is better exploited when more than two valves per cylinder are used. If two valves are used for the intake and two for the exhaust, the ratio between the overall flow area Aov and the cylinder section Acyl is now: The area rise is 30% compared to the case when only one valve is used. When more than one

9 valve per cylinder are used: - Each valve is smaller, offers a lower inertia and is easily cooled. - The valve-train is more complex, since four valves have to be driven.

### Kul Internal Combustion Engine Technology

Kul-14.4100 Internal Combustion Engine Technology Gas Exchange, 2015 Topics Gas exchange in four stroke engines Volumetric efficiency Valves and valve flow Two stroke engine scavenging Camshaft and intake

### Operating Characteristics

Chapter 2 Operating Characteristics 2-1 Engine Parameters 2-22 Work 2-3 Mean Effective Pressure 2-4 Torque and Power 2-5 Dynamometers 2-6 Air-Fuel Ratio and Fuel-Air Ratio 2-7 Specific Fuel Consumption

### Normal vs Abnormal Combustion in SI engine. SI Combustion. Turbulent Combustion

Turbulent Combustion The motion of the charge in the engine cylinder is always turbulent, when it is reached by the flame front. The charge motion is usually composed by large vortexes, whose length scales

### ACTUAL CYCLE. Actual engine cycle

1 ACTUAL CYCLE Actual engine cycle Introduction 2 Ideal Gas Cycle (Air Standard Cycle) Idealized processes Idealize working Fluid Fuel-Air Cycle Idealized Processes Accurate Working Fluid Model Actual

### SAMPLE STUDY MATERIAL

IC Engine - ME GATE, IES, PSU 1 SAMPLE STUDY MATERIAL Mechanical Engineering ME Postal Correspondence Course Internal Combustion Engine GATE, IES & PSUs IC Engine - ME GATE, IES, PSU 2 C O N T E N T 1.

### Chapter 6. Supercharging

SHROFF S. R. ROTARY INSTITUTE OF CHEMICAL TECHNOLOGY (SRICT) DEPARTMENT OF MECHANICAL ENGINEERING. Chapter 6. Supercharging Subject: Internal Combustion Engine 1 Outline Chapter 6. Supercharging 6.1 Need

### ADDIS ABABA UNIVERSITY INSTITUTE OF TECHNOLOGY

1 INTERNAL COMBUSTION ENGINES ADDIS ABABA UNIVERSITY INSTITUTE OF TECHNOLOGY MECHANICAL ENGINEERING DEPARTMENT DIVISON OF THERMAL AND ENERGY CONVERSION IC Engine Fundamentals 2 Engine Systems An engine

### STEALTH INTERNATIONAL INC. DESIGN REPORT #1001 IBC ENERGY DISSIPATING VALVE FLOW TESTING OF 12 VALVE

STEALTH INTERNATIONAL INC. DESIGN REPORT #1001 IBC ENERGY DISSIPATING VALVE FLOW TESTING OF 12 VALVE 2 This report will discuss the results obtained from flow testing of a 12 IBC valve at Alden Research

### EEN-E2002, Gas exchange and supercharging, lecture 4a

EEN-E2002, Gas exchange and supercharging, lecture 4a Basshuysen Chapter 11 Supercharging of Internal Combustion Engines Heywood Chapter 6 Gas exchange process January 2017, Martti Larmi Gas Exchange in

### VALVE TIMING DIAGRAM FOR SI ENGINE VALVE TIMING DIAGRAM FOR CI ENGINE

VALVE TIMING DIAGRAM FOR SI ENGINE VALVE TIMING DIAGRAM FOR CI ENGINE Page 1 of 13 EFFECT OF VALVE TIMING DIAGRAM ON VOLUMETRIC EFFICIENCY: Qu. 1:Why Inlet valve is closed after the Bottom Dead Centre

### Internal Combustion Engines

Engine Cycles Lecture Outline In this lecture we will: Analyse actual air fuel engine cycle: -Stroke cycle -Stroke cycle Compare these cycles to air standard cycles Actual Engine Cycle Although air standard

### Engine Heat Transfer. Engine Heat Transfer

Engine Heat Transfer 1. Impact of heat transfer on engine operation 2. Heat transfer environment 3. Energy flow in an engine 4. Engine heat transfer Fundamentals Spark-ignition engine heat transfer Diesel

### (v) Cylinder volume It is the volume of a gas inside the cylinder when the piston is at Bottom Dead Centre (B.D.C) and is denoted by V.

UNIT II GAS POWER CYCLES AIR STANDARD CYCLES Air standard cycles are used for comparison of thermal efficiencies of I.C engines. Engines working with air standard cycles are known as air standard engines.

### Module 3: Influence of Engine Design and Operating Parameters on Emissions Lecture 14:Effect of SI Engine Design and Operating Variables on Emissions

Module 3: Influence of Engine Design and Operating Parameters on Emissions Effect of SI Engine Design and Operating Variables on Emissions The Lecture Contains: SI Engine Variables and Emissions Compression

### Task 4: Read the texts, look at the illustrations and do the activities below.

Task 4: Read the texts, look at the illustrations and do the activities below. 4 BASIC OPERATIONS The Induction Stroke On the induction stroke, the inlet valve opens and the piston, moving down, creates

### Silencers. Transmission and Insertion Loss

Silencers Practical silencers are complex devices, which operate reducing pressure oscillations before they reach the atmosphere, producing the minimum possible loss of engine performance. However they

### 2.61 Internal Combustion Engines Spring 2008

MIT OpenCourseWare http://ocw.mit.edu 2.61 Internal Combustion Engines Spring 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. Engine Heat Transfer

### is the crank angle between the initial spark and the time when about 10% of the charge is burned. θ θ

ME 410 Day 30 Phases of Combustion 1. Ignition 2. Early flame development θd θ 3. Flame propagation b 4. Flame termination The flame development angle θd is the crank angle between the initial spark and

### California State University, Bakersfield. Signals and Systems. Kristin Koehler. California State University, Bakersfield Lecture 4 July 18 th, 2013

Kristin Koehler California State University, Bakersfield Lecture 4 July 18 th, 2013 1 Outline Internal combustion engines 2 stroke combustion engines 4 stroke combustion engines Diesel engines 2 Consists

### Chapter 4 ANALYTICAL WORK: COMBUSTION MODELING

a 4.3.4 Effect of various parameters on combustion in IC engines: Compression ratio: A higher compression ratio increases the pressure and temperature of the working mixture which reduce the initial preparation

### Kul Internal Combustion Engine Technology. Definition & Classification, Characteristics 2015 Basshuysen 1,2,3,4,5

Kul-14.4100 Internal Combustion Engine Technology Definition & Classification, Characteristics 2015 Basshuysen 1,2,3,4,5 Definitions Combustion engines convert the chemical energy of fuel to mechanical

### The Performance Optimization of Rolling Piston Compressors Based on CFD Simulation

Purdue University Purdue e-pubs International Compressor Engineering Conference School of Mechanical Engineering 2004 The Performance Optimization of Rolling Piston Compressors Based on CFD Simulation

### Gas exchange Processes. Typical valve timing diagram

Gas exchange Processes To move working fluid in and out of engine Engine performance is air limited Engines are usually optimized for maximum power at high speed Considerations 4-stroke engine: volumetric

### Lecture 5. Abnormal Combustion

Lecture 5 Abnormal Combustion Abnormal Combustion The Abnormal Combustion:- When the combustion gets deviated from the normal behavior resulting loss of performance or damage to the engine. It is happened

### THE FOUR STROKE CYCLE BUT HOW DOES IT WORK EXACTLY? LET S LOOK IN MORE DETAIL 1. INDUCTION SUCK 2. COMPRESSION 3. COMBUSTION 4.

THE FOUR STROKE CYCLE BUT HOW DOES IT WORK EXACTLY? WE KNOW ABOUT:- WHICH WE KNOW AS:- LET S LOOK IN MORE DETAIL 1. INDUCTION SUCK 2. COMPRESSION 3. COMBUSTION 4. EXHAUST SQUEEZE BANG BLOW Inlet valve

### Heat Transfer in Engines. Internal Combustion Engines

Heat Transfer in Engines Internal Combustion Engines Energy Distribution Removing heat is critical in keeping an engine and lubricant from thermal failure Amount of energy available for use: Brake thermal

### Best Practice Variable Speed Pump Systems

Best Practice Variable Speed Pump Systems Contents 1 Introduction 3 General Recommendations 4 2 Pumping Systems 6 3 Effects of Speed Variation 8 4 Variable Speed Drives 9 5 Financial Savings 11 Introduction

### Combustion engines. Combustion

Combustion engines Chemical energy in fuel converted to thermal energy by combustion or oxidation Heat engine converts chemical energy into mechanical energy Thermal energy raises temperature and pressure

### There are predominantly two reasons for excessive fuelling: increased fuel pressure and extended injector duration. Figure 1.0

In this tutorial we look at the actuators and components that affect the vehicles exhaust emissions when the electronically controlled fuel injection system is found to be over fuelling. There are predominantly

### CHAPTER 3 ENGINE TYPES

CHAPTER 3 CHAPTER 3 ENGINE TYPES CONTENTS PAGE Multi-Cylinders 02 Firing orders 06 2 Stroke Cycle 08 Diesel Cycle 10 Wankel Engine 12 Radial/Rotary 14 Engine Types Multi Cylinders Below are illustrated

### A Study of EGR Stratification in an Engine Cylinder

A Study of EGR Stratification in an Engine Cylinder Bassem Ramadan Kettering University ABSTRACT One strategy to decrease the amount of oxides of nitrogen formed and emitted from certain combustion devices,

### ENGINE & WORKING PRINCIPLES

ENGINE & WORKING PRINCIPLES A heat engine is a machine, which converts heat energy into mechanical energy. The combustion of fuel such as coal, petrol, diesel generates heat. This heat is supplied to a

### MIXTURE FORMATION IN SPARK IGNITION ENGINES. Chapter 5

MIXTURE FORMATION IN SPARK IGNITION ENGINES Chapter 5 Mixture formation in SI engine Engine induction and fuel system must prepare a fuel-air mixture that satisfiesthe requirements of the engine over its

### Applied Fluid Mechanics

Applied Fluid Mechanics 1. The Nature of Fluid and the Study of Fluid Mechanics 2. Viscosity of Fluid 3. Pressure Measurement 4. Forces Due to Static Fluid 5. Buoyancy and Stability 6. Flow of Fluid and

### Powertrain Efficiency Technologies. Turbochargers

Powertrain Efficiency Technologies Turbochargers Turbochargers increasingly are being used by automakers to make it possible to use downsized gasoline engines that consume less fuel but still deliver the

### Module7:Advanced Combustion Systems and Alternative Powerplants Lecture 32:Stratified Charge Engines

ADVANCED COMBUSTION SYSTEMS AND ALTERNATIVE POWERPLANTS The Lecture Contains: DIRECT INJECTION STRATIFIED CHARGE (DISC) ENGINES Historical Overview Potential Advantages of DISC Engines DISC Engine Combustion

### (a) then mean effective pressure and the indicated power for each end ; (b) the total indicated power : [16]

Code No: R05220304 Set No. 1 II B.Tech II Semester Regular Examinations, Apr/May 2007 THERMAL ENGINEERING-I ( Common to Mechanical Engineering and Automobile Engineering) Time: 3 hours Max Marks: 80 Answer

### Engine Cycles. T Alrayyes

Engine Cycles T Alrayyes Introduction The cycle experienced in the cylinder of an internal combustion engine is very complex. The cycle in SI and diesel engine were discussed in detail in the previous

### WEEK 4 Dynamics of Machinery

WEEK 4 Dynamics of Machinery References Theory of Machines and Mechanisms, J.J.Uicker, G.R.Pennock ve J.E. Shigley, 2003 Prof.Dr.Hasan ÖZTÜRK 1 DYNAMICS OF RECIPROCATING ENGINES Prof.Dr.Hasan ÖZTÜRK The

### CAPABLE OF GENERATING EFFICIENCY, TORQUE AND POWER CURVES

Predictive testing Bosch Motorsport has finally brought its much anticipated engine simulation software to market. Its author talks us through what the new package is designed to achieve By Chris van Rutten

### 2.61 Internal Combustion Engines

Due: Thursday, February 19, 2004 2.61 Internal Combustion Engines Problem Set 2 Tuesday, February 10, 2004 1. Several velocities, time, and length scales are useful in understanding what goes on inside

### I.C Engine Topic: Fuel supply systems Part-1

I.C Engine Topic: Fuel supply systems Part-1 By: Prof.Kunalsinh Kathia Essential parts of carburetor Fuel strainer Float chamber Metering and idiling system Choke and throttle Fuel strainer As gasoline

### Impacts of Short Tube Orifice Flow and Geometrical Parameters on Flow Discharge Coefficient Characteristics

Impacts of Short Tube Orifice Flow and Geometrical Parameters on Flow Discharge Coefficient Characteristics M. Metwally Lecturer, Ph.D., MTC, Cairo, Egypt Abstract Modern offset printing machine, paper

### Principles of Engine Operation. Information

Internal Combustion Engines MAK 4070E Principles of Engine Operation Prof.Dr. Cem Soruşbay Istanbul Technical University Information Prof.Dr. Cem Soruşbay İ.T.Ü. Makina Fakültesi Motorlar ve Taşıtlar Laboratuvarı

### The Internal combustion engine (Otto Cycle)

The Internal combustion engine (Otto Cycle) The Otto cycle is a set of processes used by spark ignition internal combustion engines (2-stroke or 4-stroke cycles). These engines a) ingest a mixture of fuel

### LECTURE NOTES INTERNAL COMBUSTION ENGINES SI AN INTEGRATED EVALUATION

LECTURE NOTES on INTERNAL COMBUSTION ENGINES SI AN INTEGRATED EVALUATION Integrated Master Course on Mechanical Engineering Mechanical Engineering Department November 2015 Approach SI _ indirect injection

### IC ENGINE(4 STROKE) G.H.R.I.E&M JALGAON. Sec.(Mech) Sec.(Mech) Sec.(Mech) Sec.(Mech) Mehta chirag Shah sagar Patel jainish talele amit

IC ENGINE(4 STROKE) G.H.R.I.E&M JALGAON Mehta chirag Shah sagar Patel jainish talele amit Sec.(Mech) Sec.(Mech) Sec.(Mech) Sec.(Mech) 9096297071 9028248697 9028913994 8087260063 1 Abstract The four stroke,

### EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) H4DOTC

EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) H4DOTC SYSTEM OVERVIEW 1. System Overview There are three emission control systems, which are as follows: Crankcase emission control system Exhaust emission

### Introduction to I.C Engines CH. 1. Prepared by: Dr. Assim Adaraje

Introduction to I.C Engines CH. 1 Prepared by: Dr. Assim Adaraje 1 An internal combustion engine (ICE) is a heat engine where the combustion of a fuel occurs with an oxidizer (usually air) in a combustion

### Development of Low-Exergy-Loss, High-Efficiency Chemical Engines

Development of Low-Exergy-Loss, High-Efficiency Chemical Engines Investigators C. F., Associate Professor, Mechanical Engineering; Kwee-Yan Teh, Shannon L. Miller, Graduate Researchers Introduction The

### Which are the four important control loops of an spark ignition (SI) engine?

151-0567-00 Engine Systems (HS 2017) Exercise 1 Topic: Lecture 1 Johannes Ritzmann (jritzman@ethz.ch), Raffi Hedinger (hraffael@ethz.ch); October 13, 2017 Problem 1 (Control Systems) Why do we use control

### Analysis of Parametric Studies on the Impact of Piston Velocity Profile On the Performance of a Single Cylinder Diesel Engine

IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-issn: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 2 Ver. II (Mar - Apr. 2015), PP 81-85 www.iosrjournals.org Analysis of Parametric Studies

### GASOLINE DIRECT INJECTION IN SI ENGINES B. PAVAN VISWANADH P. ASHOK KUMAR. Mobile No : Mobile No:

GASOLINE DIRECT INJECTION IN SI ENGINES SUBMIT TED BY B. PAVAN VISWANADH P. ASHOK KUMAR Y06ME011, III/IV B. Tech Y06ME003, III/IV B. Tech Pavan.visu@gmail.com ashok.me003@gmail.com Mobile No :9291323516

### 2013 THERMAL ENGINEERING-I

SET - 1 II B. Tech II Semester, Regular Examinations, April/May 2013 THERMAL ENGINEERING-I (Com. to ME, AME) Time: 3 hours Max. Marks: 75 Answer any FIVE Questions All Questions carry Equal Marks ~~~~~~~~~~~~~~~~~~~~~~~~

### Electromagnetic Fully Flexible Valve Actuator

Electromagnetic Fully Flexible Valve Actuator A traditional cam drive train, shown in Figure 1, acts on the valve stems to open and close the valves. As the crankshaft drives the camshaft through gears

### Chapter 8 Production of Power from Heat

Chapter 8 Production of Power from Heat Different sources of power, such as solar energy (from sun), kinetic energy from atmospheric winds and potential energy from tides. The most important source of

### A REVIEW OF SCAVENGING PROCESS OF TWO STROKE ENGINE

A REVIEW OF SCAVENGING PROCESS OF TWO STROKE ENGINE Prakash Kumar Sen 1, Lalit Kumar 2, Shailendra Kumar Bohidar 3 1 Student of M.Tech. Manufacturing Management, BITS Pilani (India) 2 Student of Mechanical

### Sensors & Controls. Everything you wanted to know about gas engine ignition technology but were too afraid to ask.

Everything you wanted to know about gas engine ignition technology but were too afraid to ask. Contents 1. Introducing Electronic Ignition 2. Inductive Ignition 3. Capacitor Discharge Ignition 4. CDI vs

### Module 2:Genesis and Mechanism of Formation of Engine Emissions Lecture 9:Mechanisms of HC Formation in SI Engines... contd.

Mechanisms of HC Formation in SI Engines... contd. The Lecture Contains: HC from Lubricating Oil Film Combustion Chamber Deposits HC Mixture Quality and In-Cylinder Liquid Fuel HC from Misfired Combustion

### Comparison of Swirl, Turbulence Generating Devices in Compression ignition Engine

Available online atwww.scholarsresearchlibrary.com Archives of Applied Science Research, 2016, 8 (7):31-40 (http://scholarsresearchlibrary.com/archive.html) ISSN 0975-508X CODEN (USA) AASRC9 Comparison

### UNIT IV INTERNAL COMBUSTION ENGINES

UNIT IV INTERNAL COMBUSTION ENGINES Objectives After the completion of this chapter, Students 1. To know the different parts of IC engines and their functions. 2. To understand the working principle of

### 2.61 Internal Combustion Engine Final Examination. Open book. Note that Problems 1 &2 carry 20 points each; Problems 3 &4 carry 10 points each.

2.61 Internal Combustion Engine Final Examination Open book. Note that Problems 1 &2 carry 20 points each; Problems 3 &4 carry 10 points each. Problem 1 (20 points) Ethanol has been introduced as the bio-fuel

### Design/Modeling and Thermal Analysis on Cylinder Head of I.C Engine

Design/Modeling and Thermal Analysis on Cylinder Head of I.C Engine G.Bahadur Vali Department of Mechanical, Chebrolu Engineering College. Abstract: A cylinder head is made of box type of section of considerable

### Air Management System Components

AIR M anagement Sys tem Air Management System Components Air Management System Features Series Sequential The series sequential turbocharger is a low pressure/high pressure design working in series with

### AE 1005 AUTOMOTIVE ENGINES COMBUSTION IN SI ENGINES

AE 1005 AUTOMOTIVE ENGINES COMBUSTION IN SI ENGINES Syllabus Combustion in premixed and diffusion flames - Combustion process in IC engines. Stages of combustion - Flame propagation - Flame velocity and

### I.C ENGINES. CLASSIFICATION I.C Engines are classified according to:

I.C ENGINES An internal combustion engine is most popularly known as I.C. engine, is a heat engine which converts the heat energy released by the combustion of the fuel taking place inside the engine cylinder

### three different ways, so it is important to be aware of how flow is to be specified

Flow-control valves Flow-control valves include simple s to sophisticated closed-loop electrohydraulic valves that automatically adjust to variations in pressure and temperature. The purpose of flow control

### Two Cycle and Four Cycle Engines

Ch. 5 Two Cycle and Four Cycle Engines Feb 20 7:43 AM 1 Stroke of the piston is its movement in the cylinder from one end of its travel to the other Feb 20 7:44 AM 2 Four stroke cycle engine 4 strokes

### 2) Rich mixture: A mixture which contains less air than the stoichiometric requirement is called a rich mixture (ex. A/F ratio: 12:1, 10:1 etc.

Unit 3. Carburettor University Questions: 1. Describe with suitable sketches : Main metering system and Idling system 2. Draw the neat sketch of a simple carburettor and explain its working. What are the

### SIDEWINDER COURSE PREREQUISITE MANUAL

SIDEWINDER COURSE PREREQUISITE MANUAL The S&S engine class is designed for the seasoned tech or shop owner. A certain level of knowledge and understanding is required for your success. We will be covering

### Comparative Study Of Four Stroke Diesel And Petrol Engine.

Comparative Study Of Four Stroke Diesel And Petrol Engine. Aim: To study the construction and working of 4- stroke petrol / diesel engine. Theory: A machine or device which derives heat from the combustion

### Thermal Stress Analysis of Diesel Engine Piston

International Conference on Challenges and Opportunities in Mechanical Engineering, Industrial Engineering and Management Studies 576 Thermal Stress Analysis of Diesel Engine Piston B.R. Ramesh and Kishan

### Air Cooled Engine Technology. Roth 9 th Ch 5 2 & 4 Cycle Engines Pages 81 94

Roth 9 th Ch 5 2 & 4 Cycle Engines Pages 81 94 1. The of the piston is its movement in the cylinder from one end of its travel to another. Either TDC to BDC (downstroke) or BDC to TDC (upstroke). Identified

### Technical Report Con Rod Length, Stroke, Piston Pin Offset, Piston Motion and Dwell in the Lotus-Ford Twin Cam Engine. T. L. Duell.

Technical Report - 1 Con Rod Length, Stroke, Piston Pin Offset, Piston Motion and Dwell in the Lotus-Ford Twin Cam Engine by T. L. Duell May 24 Terry Duell consulting 19 Rylandes Drive, Gladstone Park

### INTERNAL COMBUSTION ENGINE (SKMM 4413)

INTERNAL COMBUSTION ENGINE (SKMM 4413) Dr. Mohd Farid bin Muhamad Said Room : Block P21, Level 1, Automotive Development Centre (ADC) Tel : 07-5535449 Email: mfarid@fkm.utm.my HISTORY OF ICE History of

### Emission from gasoline powered vehicles are classified as 1. Exhaust emission 2. Crank case emission 3. Evaporative emission. Table 1.

Introduction: Main three types of automotive vehicle being used 1. Passenger cars powered by four stroke gasoline engines 2. Motor cycles, scooters and auto rickshaws powered mostly by small two stroke

### Technical Information

Date of last update: Sep 12 Ref: Application Engineering Europe COPELAND SCROLL COMPRESSORS USING VAPOUR INJECTION FOR REFRIGERATION CONTENTS 1 Introduction... 2 2 Principle of operation... 2 3 Capacity

### Foundations of Thermodynamics and Chemistry. 1 Introduction Preface Model-Building Simulation... 5 References...

Contents Part I Foundations of Thermodynamics and Chemistry 1 Introduction... 3 1.1 Preface.... 3 1.2 Model-Building... 3 1.3 Simulation... 5 References..... 8 2 Reciprocating Engines... 9 2.1 Energy Conversion...

### Figure 1: The spray of a direct-injecting four-stroke diesel engine

MIXTURE FORMATION AND COMBUSTION IN CI AND SI ENGINES 7.0 Mixture Formation in Diesel Engines Diesel engines can be operated both in the two-stroke and four-stroke process. Diesel engines that run at high

### AT 2303 AUTOMOTIVE POLLUTION AND CONTROL Automobile Engineering Question Bank

AT 2303 AUTOMOTIVE POLLUTION AND CONTROL Automobile Engineering Question Bank UNIT I INTRODUCTION 1. What are the design considerations of a vehicle?(jun 2013) 2..Classify the various types of vehicles.

### 2. Air Line AIR LINE FUEL INJECTION (FUEL SYSTEM) A: GENERAL B: MANIFOLD ABSOLUTE PRESSURE SENSOR FU(H4DOTC)-3

W1860BE.book Page 3 Tuesday, January 28, 2003 11:01 PM 2. Air Line A: GENERAL The air filtered by the air cleaner enters the throttle body where it is regulated in the volume by the throttle valve and

### Design and Test of Transonic Compressor Rotor with Tandem Cascade

Proceedings of the International Gas Turbine Congress 2003 Tokyo November 2-7, 2003 IGTC2003Tokyo TS-108 Design and Test of Transonic Compressor Rotor with Tandem Cascade Yusuke SAKAI, Akinori MATSUOKA,

### Modern Auto Tech Study Guide Chapter 11 Pages Engine Fundamentals 62 Points

Modern Auto Tech Study Guide Chapter 11 Pages 145-161 Engine Fundamentals 62 Points 1. The is the area between the top of the piston & the cylinder head. Combustion Chamber Cylinder Chamber Chamber of

### Influence of Cylinder Bore Volume on Pressure Pulsations in a Hermetic Reciprocating Compressor

Purdue University Purdue e-pubs International Compressor Engineering Conference School of Mechanical Engineering 2014 Influence of Cylinder Bore Volume on Pressure Pulsations in a Hermetic Reciprocating

### ENGINES ENGINE OPERATION

ENGINES ENGINE OPERATION Because the most widely used piston engine is the four-stroke cycle type, it will be used as the example for this section, Engine Operation and as the basis for comparison in the

### Internal Combustion Engines

Emissions & Air Pollution Lecture 3 1 Outline In this lecture we will discuss emission control strategies: Fuel modifications Engine technology Exhaust gas aftertreatment We will become particularly familiar

### Crankcase scavenging.

Software for engine simulation and optimization www.diesel-rk.bmstu.ru The full cycle thermodynamic engine simulation software DIESEL-RK is designed for simulating and optimizing working processes of two-

### The Influence of Port Fuel Injection on Combustion Stability

28..9 Technical The Influence of Port Fuel Injection on Combustion Stability Shoichi Kato, Takanori Hayashida, Minoru Iida Abstract The demands on internal combustion engines for low emissions and fuel

### Engine Systems. Basic Engine Operation. Firing Order. Four Stroke Cycle. Overhead Valves - OHV. Engine Design. AUMT Engine Systems 4/4/11

Advanced Introduction Brake to Automotive Systems Diagnosis Service and Service Basic Engine Operation Engine Systems Donald Jones Brookhaven College The internal combustion process consists of: admitting

### Introduction to Fuel-Air Injection Engine. (A discrete structured IC engine) KansLab

Introduction to Fuel-Air Injection Engine (A discrete structured IC engine) KansLab 1 Fig. 1: A Fuel-Air Injection (FAI) Engine is: 1) A two-stroke engine with fuel and air injections. 2) A hybrid engine

### Internal Combustion Engines

Air and Fuel Induction Lecture 3 1 Outline In this lecture we will discuss the following: A/F mixture preparation in gasoline engines using carburetion. Air Charging technologies: Superchargers Turbochargers

### EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) H6DO

EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) H6DO SYSTEM OVERVIEW 1. System Overview There are three emission control systems, which are as follows: Crankcase emission control system Exhaust emission

### Plasma Assisted Combustion in Complex Flow Environments

High Fidelity Modeling and Simulation of Plasma Assisted Combustion in Complex Flow Environments Vigor Yang Daniel Guggenheim School of Aerospace Engineering Georgia Institute of Technology Atlanta, Georgia

### Name Date. True-False. Multiple Choice

Name Date True-False T F 1. Oil film thickness increases with an increase in oil temperature. T F 2. Displacement is the volume that a piston displaces in an engine when it travels from top dead center

### Exhaust Gas CO vs A/F Ratio

Title: Tuning an LPG Engine using 2-gas and 4-gas analyzers CO for Air/Fuel Ratio, and HC for Combustion Efficiency- Comparison to Lambda & Combustion Efficiency Number: 18 File:S:\Bridge_Analyzers\Customer_Service_Documentation\White_Papers\18_CO

### SUCCESSFUL DIESEL COLD START THROUGH PROPER PILOT INJECTION PARAMETERS SELECTION. Aleksey Marchuk, Georgiy Kuharenok, Aleksandr Petruchenko

SUCCESSFUL DIESEL COLD START THROUGH PROPER PILOT INJECTION PARAMETERS SELECTION Aleksey Marchuk, Georgiy Kuharenok, Aleksandr Petruchenko Robert Bosch Company, Germany Belarussian National Technical Universitry,

### Abstract 1. INTRODUCTION

Abstract Study on Performance Characteristics of Scuderi Split Cycle Engine Sudeer Gowd Patil 1, Martin A.J. 2, Ananthesha 3 1- M.Sc. [Engg.] Student, 2-Asst. Professor, 3-Asst.Professor, Department of