Contents

Cover

Title page

Copyright page

Abstract

List of Symbols

Chapter 1: Introduction

1.1 Background
1.2 Types of Stirling Engines
1.3 Stirling Engine Designs
1.4 Free-Piston Stirling Engines
1.5 Gamma Type Engine
References and Bibliography

Chapter 2: Liquid Piston Engines

2.1 Introduction
2.2 Objectives
2.3 Brief Overview of Pumps and Heat Engines
2.4 Heat Engine
2.5 Clever Pumps
2.6 History and Development of Stirling Engines
2.7 Operation of a Stirling Engine
2.8 Working Gas
2.9 Pros and Cons of Stirling Engine
2.10 Low Temperature Difference Stirling Engine
2.11 Basic Principle of a Fluidyne
2.12 Detailed Working of a Fluidyne
2.13 Role of Evaporation
2.14 Regenerator
2.15 Pumping Setups
2.16 Tuning of Liquid Column
2.17 Motion Analysis
2.18 Losses
2.19 Factors Affecting Amplitude
2.20 Performance of Engine
2.21 Design
2.22 Assembly
2.23 Calculation
2.24 Experiments
2.25 Results
2.26 Comparison Within Existing Commercial Devices
2.27 Improvements
2.28 Future Scope
2.29 Conclusion
2.30 Numerical Analysis
References and Bibliography

Chapter 3: Customer Satisfaction Issues

3.1 Durability Issues
3.2 Testing of Engines
3.3 Design of Systems
3.4 Systems Durability
References and Bibliography

Chapter 4: Lubrication Dynamics

4.1 Background
4.2 Friction Features
4.3 Effects of Varying Speeds and Loads
4.4 Friction Reduction
4.5 Piston-Assembly Dynamics
4.6 Reynolds Equation for Lubrication Oil Pressure
4.7 Introduction
4.8 Background
4.9 Occurrence of Piston Slap Events
4.10 Literature Review
4.11 Piston Motion Simulation Using COMSOL
4.12 Force Analysis
4.13 Effects of Various Skirt Design Parameters
4.14 Numerical Model of Slapping Motion
4.15 Piston Side Thrust Force
4.16 Frictional Forces
4.17 Determination of System Mobility
4.18 Conclusion

Chapter 5: NVH Features of Engines

5.1 Background
5.2 Acoustics Overview of Internal Combustion Engine
5.3 Imperial Formulation to Determine Noise Emitted from Engine
5.4 Engine Noise Sources
5.5 Noise Source Identification Techniques
5.6 Summary
References and Bibliography

Chapter 6: Diagnosis Methodology for Diesel Engines

6.1 Introduction
6.2 Power Spectral Density Function
6.3 Time Frequency Analysis
6.4 Wavelet Analysis
6.5 Conclusion
References and Bibliography

Chapter 7: Sources of Noise in Diesel Engines

7.1 Introduction
7.2 Combustion Noise
7.3 Piston Assembly Noise
7.4 Valve Train Noise
7.5 Gear Train Noise
7.6 Crank Train and Engine Block Vibrations
7.7 Aerodynamic Noise
7.8 Bearing Noise
7.9 Timing Belt and Chain Noise
7.10 Summary
References and Bibliography

Chapter 8: Combustion Based Noise

8.1 Introduction
8.2 Background of Combustion Process in Diesel Engines
8.3 Combustion Phase Analysis
8.4 Combustion Based Engine Noise
8.5 Factors Effecting Combustion Noise
8.6 In Cylinder Pressure Analysis
8.7 Effects of Heat Release Rate
8.8 Effects of Cyclic Variations
8.9 Resonance Phenomenon
8.10 In Cylinder Pressure Decomposition Method
8.11 Mathematical Model of Generation of Combustion Noise
8.12 Evaluation of Combustion Noise Methods
8.13 Summary
References and Bibliography

Chapter 9: Effects of Turbo Charging in S.I. Engines

9.1 Abstract
9.2 Fundamentals
9.3 Turbochargers
9.4 Turbocharging in Diesel Engines
9.5 Turbocharging of Gasoline Engines
9.6 Turbocharging
9.7 Components of Turbocharged SI Engines
9.8 Intercooler
9.9 Designing of Turbocharger
9.10 Operational Problems in Turbocharging of SI Engines
9.11 Methods to Reduce Knock in S.I Engines
9.12 Ignition Timing and Knock
9.13 Charge Air Cooling
9.14 Downsizing of SI Engines
9.15 Techniques Associated with Turbo Charging of SI Engines Boosting Systems

Chapter 10: Emissions Control by Turbo Charged SI Engines

Chapter 11: Scope of Turbo Charging in SI Engines

Chapter 12: Summary

Chapter 13: Conclusions and Future Work

13.1 Conclusions
13.2 Contributions
13.3 Future Recommendations
References and Bibliography

List of Important Terms

Bibliography

Glossary

Index

End User License Agreement

List of Illustrations

Chapter 1

Figure 1.1 Alpha engines.
Figure 1.2 Beta engines.
Figure 1.3 Gamma engine.
Figure 1.4 Gamma engine.
Figure 1.5 Swash plate engines.
Figure 1.6 Rhombic drive engine.
Figure 1.7 Free piston engine.
Figure 1.8 An Alpha Stirling engine.
Figure 1.9 Alpha engine – Transfer phase.
Figure 1.10 Alpha engine - Power stroke.
Figure 1.11 Alpha engine - Transfer stroke.
Figure 1.12 Alpha engine - compression stroke.
Figure 1.13 Ross engine.
Figure 1.14 Double-acting engine.
Figure 1.15 Rocking yoke.
Figure 1.16 Gear mechanism.
Figure 1.17 Swash plate mechanism.
Figure 1.18 Beal engine.
Figure 1.19 Beta engine.
Figure 1.20 Beta engine in working.
Figure 1.21 Vertical beta engine.
Figure 1.22 Working of beta engine.
Figure 1.23 Working of beta engine – expansion.
Figure 1.24 Transfer stroke – Beta engine.
Figure 1.25 Compression stroke - beta engine.
Figure 1.26 Rhombic drive – Beta engine.
Figure 1.27 Gamma engine.
Figure 1.28 Gamma engine working.
Figure 1.29 Gamma engine – transfer stroke.
Figure 1.30 Gamma engine – expansion stroke.
Figure 1.31 Low temp engine.
Figure 1.32 Sneft engine.
Figure 1.33 Ringbom engine.
Figure 1.34 Cut out section.
Figure 1.35 Free-piston engine.
Figure 1.36 Various free engines.
Figure 1.37 Transfer stroke – free engine.
Figure 1.38 Expansion stroke – free engine.
Figure 1.39 Transfer stroke – free engine.
Figure 1.40 Compression stroke – free engine.

Chapter 2

Figure 2.1 Percentage of water sources on surface of earth.
Figure 2.2 Percentage of global population exposed to water shortage.
Figure 2.3 Percentage of population exposed to polluted water.
Figure 2.4 Sources of polluted water in underdeveloped nations.
Figure 2.5 Global groundwater withdrawal.
Figure 2.6 Solar energy balance.
Figure 2.7 Pump types.
Figure 2.8 Vane pumps.
Figure 2.9 Simple and double-acting pumps.
Figure 2.10 Discharge rates.
Figure 2.11 Peristaltic pumps.
Figure 2.12 Kinetic pumps.
Figure 2.13 Centrifugal pumps.
Figure 2.14 Jet pumps.
Figure 2.15 Performance curves.
Figure 2.16 Centrifugal pump performance curves.
Figure 2.17 Heat engine.
Figure 2.18 Energy transfer.
Figure 2.19 Heat flow.
Figure 2.20 Work efficiency.
Figure 2.21 Iso thermal process.
Figure 2.22 Perfect engine.
Figure 2.23 Energy transfer in engine.
Figure 2.24 Ideal engine.
Figure 2.25 Ideal engine P-V curve.
Figure 2.26 Human Impulse pump.
Figure 2.27 Water cellulose bonding.
Figure 2.28 Workings of a human heart.
Figure 2.29 Osmosis and reverse osmosis.
Figure 2.30 Earliest version of a Stirling engine developed by Stirling brothers.
Figure 2.31 Alpha-type Stirling engine developed in 1875.
Figure 2.32 McDonnell engine.
Figure 2.33 Heat engine.
Figure 2.34 Energy conversion in a heat engine.
Figure 2.35 P-V& T-S plot of a Carnot cycle.
Figure 2.36 P-V& T-S plot of an Otto cycle.
Figure 2.37 Stirling engine.
Figure 2.38 P-V & T-S plot of a Stirling cycle.
Figure 2.39 Comparison of Stirling cycle and Carnot cycle.
Figure 2.40 Stirling engine efficiency V/S power output for various gas.
Figure 2.41 A CHP Stirling engine.
Figure 2.42 Comparison of LTD and HTD engines.
Figure 2.43 Motion of a displacer piston in cylinder.
Figure 2.44 Motion of displacer piston towards cold side.
Figure 2.45 Motion of displacer piston towards hot side.
Figure 2.46 Motion of displacer piston and power piston.
Figure 2.47 Motion of displacer piston and power piston.
Figure 2.48 Motion of a see saw and pendulum: Gravity acts as a restoring force to bring back to mean position.
Figure 2.49 Stages of operation of a fluidyne.
Figure 2.50 Stages of operation of a fluidyne.
Figure 2.51 Stages of operation of a fluidyne.
Figure 2.52 Stages of operation of a fluidyne.
Figure 2.53 Stages of operation of a fluidyne.
Figure 2.54 General working of a fluidyne.
Figure 2.55 General working of a fluidyne.
Figure 2.56 Regenerator.
Figure 2.57 Heat exchange in a regenerator.
Figure 2.58 Pumping configurations.
Figure 2.59 Rocking beam mechanism.
Figure 2.60 Displacement of fluid in a U tube.
Figure 2.61 Variation of Beals number with source temperature.
Figure 2.62 Layout of setup.
Figure 2.63 Percentage of total volume of system.
Figure 2.64 A thermocouple.
Figure 2.65 Manometer.
Figure 2.66 Experimental setup for finding pressure and temperature.
Figure 2.67 Variation of temperature with time.
Figure 2.68 Variation of pressure with time.
Figure 2.69 Osmosis and reverse osmosis.
Figure 2.70 Variation of efficiency of pumping column with time.
Figure 2.71 Variation of power output with time.
Figure 2.72 Commercial setups for solar liquid piston engine.
Figure 2.73 Suction Phase.
Figure 2.74 Discharge phase.
Figure 2.75 Total flow.

Chapter 4

Figure 4.1 Break up of total dissipation of fuel energy.
Figure 4.2 Interpretation of Reynolds equation.
Figure 4.3 Variation of pressure along various directions.
Figure 4.4 Nodal representation of surface.
Figure 4.5 Oil pressure distribution (90° crank angle).
Figure 4.6 Oil pressure distribution (180° crank angle).
Figure 4.7 Oil pressure distribution (270° crank angle).
Figure 4.8 Oil pressure distribution (360° crank angle).
Figure 4.9 Oil pressure distribution (450° crank angle).
Figure 4.10 Oil pressure distribution (540° crank angle).
Figure 4.11 Oil pressure distribution (630° crank angle).
Figure 4.12 Oil pressure distribution (720° crank angle).
Figure 4.13 Stribeck lubrication curve.
Figure 4.14 Piston secondary motion.
Figure 4.15 Piston free body.
Figure 4.16 Piston force distribution.
Figure 4.17 Piston side thrust force (3000 RPM).
Figure 4.18 Oil film thickness behavior at 2000 RPM.
Figure 4.19 Transferred energy behavior at 2000 RPM.
Figure 4.20 Squeeze velocity of lubricant at 2000 RPM.
Figure 4.21 Time frequency analysis of filtered acceleration signals (Thrust side).
Figure 4.22 Time frequency analysis of filtered acceleration signals (Anti thrust side).
Figure 4.23 Modes of contact during piston slap.
Figure 4.24 Modes of slapping motion.
Figure 4.25 Force analysis during various modes of piston motion.
Figure 4.26 FEA Model of piston skirt (Case 1).
Figure 4.27 FEA Model of piston skirt (Case 2).
Figure 4.28 FEA Model of piston skirt (Case 3).
Figure 4.29 FEA Model of piston skirt (Case 4).
Figure 4.30 FEA Model of piston skirt (Case 5).
Figure 4.31 Velocity of piston skirt (2000 RPM).
Figure 4.32 Velocity of piston skirt (3000 RPM).
Figure 4.33 Piston skirt force balance.
Figure 4.34 Piston velocity.
Figure 4.35 Variation of Inertial force along X axis.
Figure 4.36 Variations of piston pin offset.
Figure 4.37 Variations of Top eccentricities with piston pin offset.
Figure 4.38 Variations of Bottom eccentricities with piston pin offset.
Figure 4.39 Variations of Top velocities with piston pin offset.
Figure 4.40 Variations of Bottom velocities with piston pin offset.
Figure 4.41 Variations of piston Tilt angles with piston pin offset.
Figure 4.42 Variations of piston Tilting velocities with piston pin offset.
Figure 4.43 Variations of Top eccentricities with skirt-liner gap.
Figure 4.44 Variations of Bottom eccentricities with skirt-liner gap.
Figure 4.45 Variations of Top velocities with skirt-liner gap.
Figure 4.46 Variations of Bottom eccentricities with skirt-liner gap.
Figure 4.47 Variations of Tilting angle with skirt-liner gap.
Figure 4.48 Variations of Tilting velocities with skirt-liner gap.
Figure 4.49 Variations of piston Top eccentricities with skirt length.
Figure 4.50 Variations of piston Bottom eccentricities with skirt length.
Figure 4.51 Variations of piston Tilt velocities with skirt length.
Figure 4.52 Effect of engine speed on Top eccentricities.
Figure 4.53 Effect of engine speed on Bottom eccentricities.
Figure 4.54 Effect of skirt weight on Top eccentricities.
Figure 4.55 Effect of skirt weight on Bottom eccentricities.
Figure 4.56 Effect of pin mass on Top eccentricities.
Figure 4.57 Effect of pin mass on Bottom eccentricities.
Figure 4.58 Model of Piston secondary motion.
Figure 4.59 Free body Piston diagram.
Figure 4.60 Piston side Thrust force (2000 RPM).
Figure 4.61 Piston side Thrust force (3000 RPM).
Figure 4.62 Piston velocity (3000 RPM).
Figure 4.63 Piston velocity (2000 RPM).
Figure 4.64 Piston mobility (3000 RPM).
Figure 4.65 Piston mobility (2000 RPM).
Figure 4.66 Block velocity (2000 RPM).
Figure 4.67 Block velocity (3000 RPM).
Figure 4.68 Block mobility (2000 RPM).
Figure 4.69 Block mobility (3000 RPM).
Figure 4.70 Piston tilting motion (2000 RPM-80% load)
Figure 4.71 Piston tilting motion (2000 RPM-100% Load).
Figure 4.72 Piston tiling motion (3000 RPM-Motored).
Figure 4.73 Piston tiling motion (3000 RPM-80% Load).
Figure 4.74 Piston tiling motion (3000 RPM-100% Load).
Figure 4.75 Block vibrations (2000 RPM-80% Load).
Figure 4.76 Block vibrations (2000 RPM-100%Load).
Figure 4.77 Block vibrations (3000 RPM-motored).
Figure 4.78 Block vibrations (3000 RPM-80%Load).
Figure 4.79 Block vibrations (3000 RPM-100%Load).
Figure 4.80 Piston lateral motion (2000 RPM).
Figure 4.81 Piston lateral motion (3000 RPM).

Chapter 5

Figure 5.1 Sales trend of diesel engine based automobiles in U.S.A.
Figure 5.2 Power train system.
Figure 5.3 Noise and vibration sources in engine.
Figure 5.4 In cylinder pressure spectrum.
Figure 5.5 Variations of sound pressure levels with engine speed.
Figure 5.6 Schematic representation of various sources of noise (1: Valve train, 2: Chain drive, 3–4: Accessory noise, 5: Piston slap, 6: Bearing noise, 7: Cover noise, 8: Intake noise, 9: Exhaust noise, 10: Combustion noise, 11: Oil pan noise).
Figure 5.7 Noise analysis using lead cover method.
Figure 5.8 Equal loudness contours (grey) (from ISO 226:2003 revision) original ISO standard shown (dark grey) for 40 phons.
Figure 5.9 Noise analysis using vibrational analysis method.
Figure 5.10 Engine noise model.
Figure 5.11 Application of wiener filter for estimation of combustion noise.
Figure 5.12 Dual cylinder engine noise model.

Chapter 7

Figure 7.1 Simulation of piston secondary motion.
Figure 7.2 Various bearing parameters effecting engine noise.
Figure 7.3 Schematic representation of timing chain and its noise spectra.
Figure 7.4 Timing belt transmission system(1: Sprocket, 2: Tensioner, 3: Fuel pump sprocket, 4: Crankshaft sprocket, 5: Idler sprocket, 6: Water pump sprocket).
Figure 7.5 Timing belt vibration sources.
Figure 7.6 Timing belt noise spectra.
Figure 7.7 Mechanism of noise generation.
Figure 7.8 The total noise contribution (8) can be decomposed into contributions due to combustion noise (1), contribution due to piston slap noise (2), contribution due to fan noise (3), contribution to gear operation noise (4), contribution due to pump operations (5), valve noise (6), other sources (7).

Chapter 8

Figure 8.1 Phases of diesel engine combustion.
Figure 8.2 Conventional diesel engine spray formation.
Figure 8.3 Rate of soot formation.
Figure 8.4 Soot & NO_x trade off.
Figure 8.5 Multiple injection methods adopted for modern diesel engines.
Figure 8.6 Regions of combustion noise.
Figure 8.7 Attenuation curve of engine.
Figure 8.8 Effects of heat release rate on combustion noise.
Figure 8.9 Cyclic variations in combustion noise.
Figure 8.10 Various modes of combustion chamber cavity.
Figure 8.11 Time and frequency decomposition of cylinder pressure signal.
Figure 8.12 Total decomposition of cylinder pressure signal.
Figure 8.13 Complex morlet wavelet.
Figure 8.14 Noise generation model.
Figure 8.15 AVL Structural response function and structural attenuation.
Figure 8.16 Transfer function obtained by explosive charge.
Figure 8.17 Structural attenuation function (Motored).
Figure 8.18 Structural attenuation function (1600 RPM).
Figure 8.19 Structural attenuation function (2000 RPM).
Figure 8.20 Combustion Noise – 1600 RPM.
Figure 8.21 Combustion Noise – 2000 RPM.
Figure 8.22 Use of vibration signals as a feedback for estimation of MBF50.

Chapter 9

Figure 9.1 Turbocharged C.I engine.
Figure 9.2 Sketch of a turbocharged SI-engine.
Figure 9.3 Waste-Gate Control System.
Figure 9.4 Carburetor -based turbocharger.
Figure 9.5 P-V Plot of a Naturally aspirated SI Engine.
Figure 9.6 Turbocharged SI engine.
Figure 9.7 Turbine wheel.
Figure 9.8 Velocity diagrams of compressor vane
Figure 9.9 Comprssor wheel.
Figure 9.10 Velocity diagram of compressor blade.
Figure 9.11 P-V curve of a turbocharged S.I.Engine.
Figure 9.13 Turbocharger with VGT.
Figure 9.14 Exhaust gases recirculation system assembly for naturally aspirated (a) and turbocharged (b) – System components: 1 humidity’ separator; 2 booster; 3 EGR valve; 4 single point injection; 5 heat exchanger: 6 compressor: 7 single point injection and equalization box: S turbine.

List of Tables

Chapter 2

Table 2.1 Comparison of various engines.
Table 2.2 Comparison of properties of various materials for regenerator [15].
Table 2.3 Value of kinetic energy loss factor for various configurations [21].
Table 2.4 Comparison of various design choices.
Table 2.5 Volume occupied by various parts.
Table 2.6 Variation of pressure and temperature of air with time.
Table 2.7 Variation of stroke length with time.
Table 2.8 Variation of efficiency of pumping column with time.
Table 2.9 Performance parameters of existing engines.
Table 2.10 Comparison of irrigation costs for various methods.
Table 2.11 Comparison of pumping costs and efficiency of various methods.
Table 2.12 Comparison of emissions.

Chapter 4

Table 4.1 Summary of slap events (Lateral force method).
Table 4.2 Engine parameters.
Table 4.1 Dynamic parameters of system.

Chapter 5

Table 5.1 Supply of diesel engines by various manufacturer, Year-2013.
Table 5.2 Frequency ranges of various noise sources.
Table 5.3 Noise analysis from a V6 engine.

Chapter 9

Table 9.1 Comparison: Spark-ignition and diesel engine.
Table 9.2 Comparison of naturaly aspirated & turbo-charged BMP C.I engine (15.9 Litres at ambient temperature 28 °C & humidity 61%) Ref: V.R.D.E. MAGAZINE.

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Library of Congress Cataloging-in-Publication Data
ISBN 978-1-119-32295-5

Abstract

Engines and pumps are common engineering devices which have become essential to the smooth running of modern society. Many of these are very sophisticated and require infrastructure and high levels of technological competence to ensure their correct operation. For example, some are computer controlled, others require stable three-phase electrical supplies, or clean hydrocarbon fuels. The first part of the project focuses on the identification, design, construction and testing of a simple, yet elegant, device which has the ability to pump water but which can be manufactured easily without any special tooling or exotic materials and which can be powered from either combustion of organic matter or directly from solar heating.

The device, which has many of the elements of a Stirling engine, is a liquid piston engine in which the fluctuating pressure is harnessed to pump a liquid (water). A simple embodiment of this engine/pump has been designed and constructed. It has been tested and recommendations on how it might be improved are made. The underlying theory of the device is also presented and discussed.

The second portion deals with noise, vibration and harshness performances of internal combustion engines. Features of various sources of noise and vibrations have been discussed and major focus has been on combustion based noise and piston secondary motion. Various equations of piston motion were solved and effects of various parameters on it were analyzed.

Symbol	Definition	Units
V	Volume	cm³
P	Pressure	Bar
T	Temperature	Kelvin
R	Gas Constant	J/K-mol
v	Voltage	Volt
I	Current	Ampere
Q, V′	Volume flow Rate	cm³/s
Q_e	Heat Absorbed	Joules
A	Tube Area	cm²
q	Charge	coulomb
C_p	Specific Heat	J/Kg-K
η	Kinematic Fluid Viscosity	m²/S
ω	Frequency	Hz
R_t	Radius Of Tube	cm
X	Fluid Displacement	cm
ρ	Fluid Density	kg/m³
U	Heat Transfer coefficient	W/m²-k
L,l	Tube length	cm
g	Acceleration due to gravity	m/s²

Symbol

Definition

Units

Volume

cm³

Pressure

Bar

Temperature

Kelvin

Gas Constant

J/K-mol

Voltage

Volt

Current

Ampere

Q, V′

Volume flow Rate

cm³/s

Q_e

Heat Absorbed

Joules

Tube Area

cm²

Charge

coulomb

C_p

Specific Heat

J/Kg-K

Kinematic Fluid Viscosity

m²/S

Frequency

R_t

Radius Of Tube

Fluid Displacement

Fluid Density

kg/m³

Heat Transfer coefficient

W/m²-k

L,l

Tube length

Acceleration due to gravity

m/s²