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Transcript of Engine Technology Progress In Japan - Spark-Ignition Engine Technology
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ENGINETECHNOLOGY
PROGRESSINJAPAN
ARIGA TECHNOLOGIES
Bremerton, Washington, U.S.A.
October 2014
SPARK-IGNITION
ENGINETECHNOLOGY
ISSN 1085-6900
1.0 INVESTIGATIONINTOPRE-IGNITIONPHENOMENAINAHIGHLYBOOSTED
SI GASOLINEENGINE
2.0 PRE-IGNITIONPREVENTIVECONTROLSYSTEMDEVELOPEDFORA
DI GASOLINEENGINEWITHAHIGH-COMPRESSIONRATIO
3.0 TECHNICALAPPROACHESDEVELOPEDTOIMPROVEDI GASOLINECOMBUSTION
OVERAWIDEOPERATINGRANGE
4.0 IRRADIATIONOFPREMIXFUELWITHPULSEDDIELECTRICBARRIERDISCHARGETOCONTROLPCI COMBUSTION
5.0 APPLICATIONOFALOW-PRESSURE-LOOPEGR SYSTEMTOA
HIGHLYBOOSTEDDOWNSIZEDGASOLINEENGINE
6.0 CHARACTERIZATIONOFFRICTIONANDOILCONSUMPTIONFORA
TWO-PIECEOILCONTROLRING
7.0 MEASUREMENTOFOILFILMPRESSUREATTHEPISTONPINFOR
IMPROVEMENTOFSIMULATION
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Copyright 1994~2014ARIGA TECHNOLOGIES. All rights reserved.
All portions of this publication are protected against copying or other reproduction by an individual
or any organization regardless of either internal or external organizational use without prior
approval fromARIGA TECHNOLOGIES.
Neither ARIGA TECHNOLOGIES nor any other person acting on behalf of ARIGA
TECHNOLOGIESassumes liability for any loss or damage of any kind resulting from the use
of the information contained in this document or any errors or omissions in any entry.
ARIGA TECHNOLOGIES
Bremerton, Washington, U.S.A.
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PREFACE
ARIGA TECHNOLOGIES (AT) (formerly inter-
Tech Energy Progress, Inc.) in cooperation with
the Society of Automotive Engineers of Japan is
totally dedicated to contribute to an increasedflowof engine technological data from Japan and assist
engine engineers in foreign countries in maintaining
an awareness of Japanese engine technology
progress. The professionals at ATare committed
to accomplish the above objectives.
ATpublishes two reports per year in April and
October each on the following three disciplines.
Alternative Fuels and Engines
Compression-Ignition Engine Technology
Spark-Ignition Engine Technology
Each semiannual report consists of threeparts; 1) executive summary for a quick reference
of the report contents, 2) main body of the report
summarized and organized into similar topics, and
3) a list of literature referenced in the report. The
report is written to inform the reader of the valuable
essence of referenced literature sources available
through engineering societies and technical
periodicals in Japan. AT screens the literature,
analyzes the contents, and selects them for the
report. We write the report in our own words so that
readers can efficiently acquire the most valuable
information. Yet, the report contains sufficient
technical data including tables and figures usefulfor engineering study on each topic. Therefore, the
report is just not an assembly of literature directly
translated from Japanese into English. The report
is well organized for the selected topics and is a
stand alone technical document.
We greatly appreciate your comments and
suggestions on the contents of the report. Therefore,
please feel free to contactAT.
Thank you very much for your interest in "ENGINE
TECHNOLOGYPROGRESSINJAPAN" .
ARIGA TECHNOLOGIES8011 Tracyton Blvd. NWBremerton, Washington 98311-9066, U.S.A.
Telephone: 210-408-7508
Facsimile: 210-568-4972
email: [email protected]
www.arigatech.com
ENGINETECHNOLOGYPROGRESSINJAPAN
PUBLISHER
Susumu Ariga
Editor / Consulting Engine Engineer
ARIGA TECHNOLOGIES
Bremerton, Washington, U.S.A.
TECHNICAL ADVISORY BOARD
Mr. Brent K. BaileyExecutive Director
Coordinating Research Council, Inc.
Alpharetta, Georgia, U.S.A.
Emeritus Prof. Takeyuki Kamimoto,Ph.D.Tokyo Institute of Technology, Tokyo, Japan
Co-Chairman of Engineering Foundation
Conference 1991 and 1993
Fellow of SAE
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EXECUTIVE
SUMMARY
v Copyright2014ARIGA TECHNOLOGIES
1.0 INVESTIGATIONINTOPRE-IGNITION
PHENOMENAINAHIGHLYBOOSTEDSI
GASOLINEENGINE
Engine Tests Demonstrate Contributions
of Multiple Processes in Pre-Ignition(ETPJ No. 32014101): Downsizing and
supercharging have become common
technical approaches to improve fuel
economy and performance in recent
automotive gasoline engines while exhaust
emissions have been kept low. Pre-ignition
has become an issue, however, as these
approaches increase specific power output
especially when the engine operates under
high load at low speeds. Although pre-
ignition rarely occurs (only once per several
thousands of engine cycles), combustionknock is often produced along with pre-
ignition. Thus, power cylinder components
are stressed by extremely high cylinder
pressure and temperature which may lead to
catastrophic failure of engine components.
Engineers at Nippon Soken, Inc., and
Toyota Motor Corporation observed pre-
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ENGINETECHNOLOGYPROGRESSINJAPAN
Copyright 2014ARIGA TECHNOLOGIES
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
ignition and related phenomena to better understand
how pre-ignition occurs. A 1.997-liter, inline four-
cylinder, direct-injection (DI) gasoline engine was
modified by installation of optical access to the
combustion chamber of one of the four cylinders.
Pre-ignition, in most cases, initiated from particlesfloating in the gas, and the mixture ignited by the
particles burned in flame propagation. As a test
to validate this pre-ignition triggered by particles,
deposits removed from the combustion chamber were
artificially re-introduced into the combustion chamber.
Pre-ignition occurred similarly to that observed in the
test engine operating under high load at low speed.
Additionally, the engine was intentionally operated
with combustion knock, which caused deposits to flake
off the combustion chamber walls. Consequently, a
significant quantity of particles
floated in the gas.These particles became sources of pre-ignition in the
following cycle. Thus, deposits from the combustion
chamber wall contributed to pre-ignition.
Fuel injection timing was varied to increase the
amount of fuel impinging on the cylinder wall in
order to observe whether this fuel would affect pre-
ignition. Engine operation with fuel spray impinging
on the cylinder wall indeed produced deposits on
the combustion chamber walls. A portion of these
deposits flaked off, and the particles floated in the
gas. The floating particles were then exposed
to combustion flame and heat, thus burning andincreasing temperature.
During the expansion and exhaust strokes, the
particles were cooled and sustained in the cylinder as
unburned particles. Although the particles no longer
burned, they continued to oxidize with the oxygen in
the gas. Then, fresh charge during the intake stroke
enhanced oxidation of the particles. As the gas was
compressed during the compression stroke, oxidation
of the particles was further accelerated, causing
the particles to start burning again. The particles
became red hot and produced sufficient energy toignite mixture in the vicinity of the particles. When
this occurred prior to spark ignition, the mixture ignited
and flame propagated, causing cylinder pressure to
rapidly increase during the compression stroke.
This study demonstrates that pre-ignition involves
multiple processes before it actually occurs. The
process not only involves particles from various
materials, i.e., fuel, oil, particulate matter, etc., but
VIEWAREA
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Copyright2014ARIGA TECHNOLOGIES
SPARK-IGNITIONENGINETECHNOLOGY
also multiple engine cycles.
This chapter reports observation results of
pre-ignition phenomena through visualization of a
combustion chamber in a production DI gasoline
engine and characterizes the process in which pre-
ignition was induced.
2.0 PRE-IGNITIONPREVENTIVECONTROLSYSTEM
DEVELOPEDFORADI GASOLINEENGINEWITHA
HIGH-COMPRESSIONRATIO
Engine Tests Confirm Function of Control System
to Eliminate Pre-Ignition (ETPJ No. 32014102): In
addition to downsizing and supercharging, increasing
compression ratio has become an additional
technical approach to improve fuel economy and
engine performance. The challenge with increasedcompression ratio is preventing abnormal combustion
such as pre-ignition and combustion knock; otherwise,
the engine cannot take full advantage of the higher
compression ratio to improve the engine performance.
In an engine with a higher combustion ratio,
abnormal combustion is sensitive to changes in
engine operating conditions, i.e., ambient temperature
and fuel quality depending on geographic locations.
To prevent abnormal combustion, valve timing can
be controlled to adjust the effective compression
ratio so that the engine operates free of combustion
knock. However, clear understanding of the multiple
factors that lead to abnormal combustion is necessary
so that the engine is designed to operate with the
maximum allowable compression ratio, thus taking
full advantage of the benefits of using a higher
compression ratio.
Engineers at Mazda Motor Corporation
investigated pre-ignition phenomena in a test
engine with a higher compression ratio under various
engine operating conditions. Based on the results,
they developed a model to predict the effective
compression ratio that would allow engine operationwithout pre-ignition and integrated it with an intake
valve control system.
An engine was tested with various intake charge
temperatures to observe the effect of change in the
ambient temperature at various geographic locations,
and the effect on torque was observed for the
compression ratios of 10 and 15. Regardless of the
compression ratio, torque decreased as the intake
THEEFFECTOFSPARKTIMINGON
RELATIVETORQUEFORDIFFERENT
COMPRESSIONRATIOS
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ENGINETECHNOLOGYPROGRESSINJAPAN
Copyright 2014ARIGA TECHNOLOGIES
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
charge temperature was reduced, and the rate of
reduction in engine torque was almost the same.
As the intake charge temperature was increased,
the engine control system retarded spark timing to
prevent combustion knock. The level of timing retard
was greater in the engine with a lower compressionratio. In the engine with a higher compression
ratio, the spark timing was already retarded and the
level of timing retard was minimal. Peak cylinder
pressure in the engine with a higher compression
ratio became lower since the combustion mainly
occurred during the expansion stroke. So even
though the intake temperature was increased, the
rate of reduction in torque became about the same
for both compression ratios because of the negative
temperature dependence.
A 2-liter, inline four-cylinder, DI gasoline enginewas operated under various field conditions at various
geographic locations and data were acquired to
characterize the relationship between peak heat
release rate and mass burn fraction (MBF) 10 percent.
The above relationship was used to determine
the safe operating range in which pre-ignition was
suppressed. Multiple regression analysis was
performed to develop a model. The model was then
incorporated with the control system for intake valve
closure timing.
The engine equipped with the above control
system was tested in the field in both China andNorth America. Research octane number (RON) of
the fuel in China was as low as 88.2, and the higher
intake charge temperature was 85C. These values
were outside the range used for the engine operating
conditions when the engine was tested to acquire data
for constructing the model. However, the engine did
not experience pre-ignition, and no catastrophic failure
was found in the engine components. Therefore, the
pre-ignition preventive control system performed well
to suppress pre-ignition in the engine operated even
under harsh operating conditions. This chapter reports characterization results of
torque and combustion knock in a test engine with
both low and high compression ratios and a control
system to adjust the effective compression ratio.
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October 2014
Copyright2014ARIGA TECHNOLOGIES
SPARK-IGNITIONENGINETECHNOLOGY
3.0 TECHNICALAPPROACHESDEVELOPEDTO
IMPROVEDI GASOLINECOMBUSTIONOVERA
WIDEOPERATINGRANGE
Guide Wall and Piston Crown Design Demonstrate
Optimal Gas Motion (ETPJ No. 32014103): A DI
gasoline engine with supercharging and downsizing
has the potential to further improve torque, fuel
economy, and exhaust emissions over a wide
operating range through optimization of combustion
chamber shape, intake port configuration, and
fuel spray orientation. Engineers at Toyota Motor
Corporation report their latest developments for a
turbocharged DI gasoline engine. As a result of
these developments, stable warm-up operation more
effectively reduced exhaust gas emissions, and
maximum power output increased by 4.7 percent. Both the piston crown and intake port were
configured to enhance tumble flow with increased
turbulence intensity for high power output while
mixture was effectively stratified to achieve stable
combustion during engine warm-up. Key elements
to successfully achieving improvements for both
operating conditions were the technical approaches
taken to craft the gas flow pattern in the cylinder during
both intake and compression strokes. Visualization
of combustion in an optical engine and numerical
analysis provided information useful to optimizing
configurations of both the combustion chamber and
intake port.
As a result, the cavity opening in the piston crown
was increased to enhance gas motion in the cylinder,
and a guide wall was made to retain the original cavity
shape. The guide wall helps stratify mixture near the
spark plug during engine warm-up while the wider
opening of the entire cavity enhances gas motion to
produce homogeneous mixture under full load.
The intake port was designed to produce a
higher tumble ratio which increased turbulence
intensity when the tumble flow destructed as thepiston approached top dead center. The tumble
ratio measured on a steady-state flow test rig did
not correlate with the measured engine power output
and the calculated turbulence intensity. Both the
intake port and combustion chamber require design
optimization so that they complement each other
to achieve the design targets. Through the above
optimizations, the newly designed piston crown
NEWLYDESIGNEDPISTONCROWN
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ENGINETECHNOLOGYPROGRESSINJAPAN
Copyright 2014ARIGA TECHNOLOGIES
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
combined with the above intake port effectively
improved tumble flow characteristics and increased
turbulence intensity while stratification of mixture
necessary for accelerating the aftertreatment devices
was effectively produced during engine warm-up.
This chapter reports the systematic approachestaken to improve the combustion of a turbocharged
DI gasoline engine both during warm-up and under
full-load operation.
4.0 IRRADIATIONOFPREMIXFUELWITHPULSED
DIELECTRICBARRIERDISCHARGETOCONTROL
PCI COMBUSTION
Use of Non-thermal Plasma Studied for Enhanced
Chemical Reaction of Fuel (ETPJ No. 32014104):
Combustion of premix fuel via premix compressionignition (PCI) depends on the chemical reaction rate
during the pre-flame reaction process prior to self-
ignition. The chemical reaction rate varies due to
such factors as air/fuel ratio, temperature, and the
fuels chemical components. A method to control
the chemical reaction rate of premix fuel may be
able to adjust the timing for the mixture to self-ignite.
Thus, the combustion rate is controlled appropriately
depending on engine operating conditions, and the
inherently narrow operating range of PCI combustion
may be expanded and overall engine performance
and exhaust emissions may be improved.
Researchers at the National Institute of Advanced
Industrial Science and Technology (AIST) and
Tsukuba University have been investigating the
potential of using non-thermal plasma to enhance
the chemical reaction of fuel mixture as a method to
control PCI combustion. Irradiating premix fuel with
non-thermal plasma advances the timing of self-
ignition during the compression stroke. Stratifying
the irradiated mixture in the combustion chamber can
change the timing of self-ignition and control the rate
of pressure rise after the mixture self-ignites.By use of a rapid compression machine (RCEM),
various fuels including normal heptanes, methyl
cyclohexane, and toluene were tested to characterize
the effect of applying non-thermal plasma on self-
ignition. A pulsed dielectric barrier discharge (DBD)
plasma reactor was used to apply non-thermal plasma
to premix fuel. The irradiation duration was changed
to evaluate response of premix fuels self-ignition.
PULSEDDBD REACTOR
http://www.arigatech.com/spark-ignition-engine-technology/irradiation-of-premix-fuel-with-pulsed-dielectric-barrier-discharge-to-control-pci-combustionhttp://www.arigatech.com/spark-ignition-engine-technology/irradiation-of-premix-fuel-with-pulsed-dielectric-barrier-discharge-to-control-pci-combustion -
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Copyright2014ARIGA TECHNOLOGIES
SPARK-IGNITIONENGINETECHNOLOGY
The other parameters included excess air ratio, initial
temperature of premix fuel, and compression ratio.
N-heptane mixture self-ignited 55 milliseconds
after compression started. By irradiating the mixture
for 1 second, the start of combustion was advanced
to 45 milliseconds, and the combustion pressurereduced fluctuation near the peak. Increasing the
duration of irradiation to 16 seconds further advanced
the start of combustion, but the combustion pressure
significantly fluctuated more than the combustion of
the mixture with no irradiation. Leaner mixture also
responded to the duration of irradiation, and the start
of combustion was advanced. However, the start of
combustion did not linearly advance depending on
the duration of irradiation.
Methyl cyclohexane and toluene required higher
initial temperature and higher compression ratio,respectively, to self-ignite. Because of the differences
in chemical composition and self-ignition temperature
among the three fuels, each responded differently to
irradiation.
This chapter reports the experimental results of
combustion with non-thermal plasma and self-ignition
characteristics of three different fuels having different
self-ignition temperature.
5.0 APPLICATIONOFALOW-PRESSURE-LOOPEGR
SYSTEMTOAHIGHLYBOOSTEDDOWNSIZED
GASOLINEENGINE
LPL-EGR Demonstrates Advantages Compared
to HLP and MP Systems (ETPJ No. 32014105):
Downsizing and turbocharging have significantly
improved gasoline engine performance and fuel
economy. Improvement of combustion under
frequent turbocharged operation can further reduce
fuel consumption particularly under high loads at low
speeds, according to engineers at Nissan Motor Co.,
Ltd. Among the approaches taken to accomplish
these improvements was a cooled exhaust gasrecirculation (EGR) system designed to suppress
combustion knock, reduce exhaust gas temperature,
and increase specific heat ratio of the intake charge.
EGR gas was drawn from a location downstream
of the catalysts in the exhaust system and recirculated
into the intake system upstream from the compressor
of the turbocharger. This low-pressure-loop EGR
(LPL-EGR) system had several advantages overEGR SYSTEMS
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ENGINETECHNOLOGYPROGRESSINJAPAN
Copyright 2014ARIGA TECHNOLOGIES
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
a high-pressure-loop EGR (HPL-EGR) system
and a mixed-pressure EGR (MP-EGR). The EGR
gas supply range was wider toward the operating
range of high load at low speed. Combustion knock
tolerance was improved by lower nitrogen oxides
(NOx) content in the EGR gas drawn from a locationdownstream of the three-way catalyst. Also, the
temperature of exhaust gas downstream from the
catalysts is relatively low and can further be reduced
by advancing spark timing.
The LPL-EGR system was designed to reduce
flow restriction and a pressure transducer was used
to monitor the pressure across the EGR valve. Under
steady-state operating conditions, the EGR rate at a
given EGR valve position is independent of the intake
air flow rate. A control algorithm was developed
to compensate for the change in the exhaust gaspressure during vehicle deceleration so that the EGR
rate can be maintained at constant.
This chapter reports pros and cons of three EGR
systems and the design of the LPL-EGR system with
an EGR cooler for a turbocharged gasoline engine.
6.0 CHARACTERIZATIONOFFRICTIONANDOIL
CONSUMPTIONFORATWO-PIECEOILCONTROL
RING
Oil Control Rings Compared for Friction and Oil
Consumption (ETPJ No. 32014106):A piston ring
pack generally consists of two compression rings and
one oil control ring and shares a significant portion
of the friction generated by a piston. Among the
three piston rings, the oil control ring is designed for
the purpose of removing excess oil off the cylinder
wall, and the tension is generally set higher (i.e.,
about 3 to 5 folds compared to compression rings).
Thus, reducing the tension of the oil control ring
effectively decreases piston friction; however, lower
ring tension causes oil consumption to increase.
Because of this trade-off relationship between frictionand oil consumption, reduction in this ring tension is
somewhat limited.
Lubricating conditions at the interface of a piston
ring with a cylinder wall is sensitive to the shape of
the sliding surface of the piston ring and the texture of
the cylinder wall. Because the thickness of the oil film
is small, on the order of microns, a small change in
the shape significantly changes the oil film thickness;
RECIPROCATINGTESTRIGTO
MEASUREFRICTIONALFORCEOFAN
OILCONTROLRING
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Copyright2014ARIGA TECHNOLOGIES
SPARK-IGNITIONENGINETECHNOLOGY
namely, both friction and oil consumption can
significantly change. On the other hand, if the sliding
surface of the piston ring is properly configured, both
friction and oil consumption may further be reduced
even with the lowest possible ring tension.
Engineers at Riken Corporation reported theresults of parametric tests conducted to characterize
the effect the sliding surface shape and width on both
friction and oil consumption focusing on a two-piece
oil control ring. The frictional force was measured
using a reciprocating test rig while oil consumption
was measured in a test engine. With calculated
frictional force and oil film thickness, the data were
characterized and discussed.
Three oil control ring types were prepared for the
characterization. The ring that had a small radius
on the edge of both upper and lower rails performedwell and decreased both friction and oil consumption.
This narrow barrel-shaped sliding surface effectively
decreased oil film pressure, leading to the thinner
oil film particularly in the middle stroke. Hence, the
frictional force generated during the entire engine
cycle could be reduced. The thinner oil film was
determined to be the reason for lower oil consumption.
This chapter reports the results of parametric tests
conducted for three two-piece oil control ring types
and discussion of the results.
7.0 MEASUREMENTOFOILFILMPRESSUREATTHEPISTONPINFORIMPROVEMENTOFSIMULATION
Linear System Analysis and EHL Compared for
Accuracy of Simu lation (ETPJ No. 32014107):
Computer-aided design (CAE) has successfully
enabled optimization of design parameters for a
reliable and durable piston and accelerated the
design process for production pistons, yet simulation
models to predict strength of the piston pin and boss
still need improvement. The general approach to
simulate the piston pin and piston pin boss has beento calculate contact pressure at the interface of the
sliding surfaces without taking account of lubrication
effects, according to researchers at both ART Metal
and Tokyo City University.
Elasto-hydrodynamic lubrication (EHL) theory is
commonly used to simulate lubrication of the sliding
surfaces of the journal bearing, cam robe, piston pin,
etc. In simulating oil film pressure with the lubrication
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ENGINETECHNOLOGYPROGRESSINJAPAN
Copyright 2014ARIGA TECHNOLOGIES
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
theory, there are still several unknown factors
that influence the calculation results. Therefore,
researchers measured oil film pressure using a test
rig and compared the results with the calculations to
evaluate the accuracy of simulated oil film pressure
by two methods: (1) linear system analysis and (2)EHL analysis. Linear system analysis has generally
been used to evaluate the durability performance of
both the piston pin and piston pin boss, but it does
not include lubrication analysis.
A thin-film oil pressure sensor was used to
measure the pressure of the oil film in the clearance
between the piston pin and piston pin boss. At least
three sensors were installed on the piston pin along
its center axis. Several piston pins with sensors were
prepared and each pin was tested to measure oil film
pressure approximately every 1 mm between eachend of the piston pin boss so that the distribution of
oil film pressure along the piston pin axis could be
evaluated.
The piston was cyclically loaded with hydraulic
pressure to simulate cylinder pressure force in an
engine. Two piston pin boss shapes were tested
to evaluate the effect of the taper angle of the inner
end of the piston pin boss on the distribution of oil
film pressure. The calculated oil film pressure with
the linear system analysis correlated well with the
measured result in terms of the distribution of oil film
pressure along the piston pin axis, although somedifferences were observed between calculation and
measurement in both peak pressure and pressure at
the taper section of the piston pin boss.
The EHL analysis was inaccurate, however.
Both distribution and the level of pressure were quite
different between calculation and measurement.
Conditions used for the EHL analysis were suspected
to be different from those of lubrication in the actual
piston tested on the test rig. Thus, the EHL analysis
will need improvement on the assumption that the
measured oilfilm pressure was correct, according toresearchers.
This chapter describes the thin-film oil pressure
sensor, test method, calculation methods, and results
of comparison between measurement and calculation.
WHEATSTONEBRIDGESETUPFORA
THIN-FILMOILPRESSURESENSOR
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TABLE OF CONTENTSPage
ACKNOWLEDGMENTS ........................................................................................... ii
PREFACE................................................................................................................. ii i
EXECUTIVE SUMMARY ...........................................................................................v
TABLE OF CONTENTS .......................................................................................... xv
1.0 INVESTIGATIONINTOPRE-IGNITIONPHENOMENAINAHIGHLYBOOSTED
SI GASOLINE
ENGINE
.............................................................................................. 1
1.1 OBSERVATION AND CHARACTERIZATION OF PRE-IGNITION ................ 2
1.1.1 Pre-Ignition Phenomena ....................................................................3
1.1.2 Pre-Ignition Caused by Deposits ......................................................... 8
1.1.3 Fuel-Diluted Oil and Deposits ........................................................... 11
2.0 PRE-IGNITIONPREVENTIVECONTROLSYSTEMDEVELOPEDFORA
DI GASOLINEENGINEWITHAHIGH-COMPRESSIONRATIO............................. 15
2.1 A MODEL-BASED CONTROL SYSTEM DEVELOPED TO PREVENT
PRE-IGNITION ............................................................................................. 16
2.1.1 Power Output at High Temperature .................................................. 16
2.1.2 Pre-Ignition ........................................................................................21
3.0 TECHNICALAPPROACHESDEVELOPEDTOIMPROVEDI GASOLINE
COMBUSTIONOVERAWIDEOPERATINGRANGE ............................................... 27
3.1 COMBUSTION CHAMBER AND INTAKE PORT DESIGN
OPTIMIZATIONS ..........................................................................................28
3.1.1 Spray Angle .......................................................................................30
3.1.2 Power Output of a Prototype Engine .................................................33
3.1.3 Warm-Up Period ............................................................................... 34
3.2 Optimization of Combustion System Specifications ............................... 35
3.2.1 Guide Wall Location ..........................................................................35
3.2.2 Intake Port and Combustion Chamber Shape ..................................38
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TABLE OF CONTENTS(cont'd.)
Page
4.0 IRRADIATIONOFPREMIXFUELWITHPULSEDDIELECTRICBARRIER
DISCHARGETOCONTROLPCI COMBUSTION ..................................................... 43
4.1 CHARACTERIZATION OF THE NON-THERMAL PLASMA-ASSISTED
CHEMICAL REACTION PROCESS .............................................................44
4.1.1 Test Apparatus and Procedure .......................................................... 44
4.1.2 Test Results .......................................................................................46
5.0 APPLICATIONOFALOW-PRESSURE-LOOPEGR SYSTEMTOAHIGHLY
BOOSTEDDOWNSIZEDGASOLINEENGINE......................................................... 51
5.1 LPL-EGR SYSTEM WITH AN EGR COOLER ............................................. 52
5.1.1 Cooled EGR ......................................................................................53
5.1.2 LPL-EGR System ..............................................................................56
5.1.3 EGR Control ......................................................................................58
6.0 CHARACTERIZATIONOFFRICTIONANDOILCONSUMPTIONFORA
TWO-PIECEOILCONTROLRING .........................................................................61
6.1 FRICTION AND OIL CONSUMPTION CHARACTERIZED FOR VARIOUS
SHAPES OF THE SLIDING SURFACES OF AN OIL CONTROL RING ..... 62
6.1.1 Friction and Oil Consumption Measurement Results ........................63
6.1.2 Friction and Oil Film Thickness ......................................................... 64
7.0 MEASUREMENTOFOILFILMPRESSUREATTHEPISTONPINFOR
IMPROVEMENTOFSIMULATION ..............................................................................71
7.1 MEASUREMENT AND CALCULATION OF OIL FILM PRESSURE ...........72
7.1.1 Technical Approaches .......................................................................72
7.1.2 Piston Pin Oil Film Pressure .............................................................77
REFERENCES ....................................................................................................................... 81
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Copyright2014ARIGA TECHNOLOGIES
SPARK-IGNITIONENGINETECHNOLOGY
REFERENCES
NOTE: English titles are provided by the original authors.
* JSAE: Society of Automotive Engineers of Japan
1.0 INVESTIGATION
INTO
PRE
-IGNITION
PHENOMENAINAHIGHLYBOOSTEDSI
GASOLINEENGINE
Izumi, Y., F. Aoki, and M. Iizuka, Nippon
Soken, Inc., and Y. Okada, Toyota Motor
Corporation, Optical Analysis of Low-
Speed Pre-Ignition on Highly Boosted
SI Engine,JSAE* Paper No. 20145032,
May 2014.
2.0 PRE-IGNITIONPREVENTIVECONTROL
SYSTEMDEVELOPEDFORA DIGASOLINEENGINEWITHAHIGH-
COMPRESSIONRATIO
Shishime, K., M. Ohashi, T. Youso, and M.
Yamakawa, Mazda Motor Corporation,
Study of Robustness for Practical Use
of Gasoline High Compression Ratio
Engine,JSAE Paper No. 20145351,
May 2014.
3.0 TECHNICALAPPROACHESDEVELOPEDTOIMPROVEDI GASOLINE
COMBUSTIONOVERAWIDE
OPERATINGRANGE
Mitani, S., S. Hashimoto, H. Nomura, R.
Shimizu, and M. Kanda, Toyota Motor
Corporation, Toyota New Combustion
Concept for Turbocharged Direct-
Injection Engines,JSAE 20145036,
May 2014.
4.0 IRRADIATIONOFPREMIXFUELWITH
PULSEDDIELECTRICBARRIERDISCHARGE
TOCONTROLPCI COMBUSTION
Takahashi, E., H. Kojima, T. Segawa,
and H. Furutani, National Institute
of Advanced Industrial Science and
Technology (AIST); and S. Yamaguchi
and T. Kashiwazaki, Tsukuba University,
Control of Compression Ignition by
Dielectric Barrier Discharge, JSAE
Paper No. 20145088, May 2014.
5.0 APPLICATIONOFALOW-PRESSURE-
LOOPEGR SYSTEMTOAHIGHLY
BOOSTEDDOWNSIZEDGASOLINE
ENGINE
Yoshida, S., M. Kobayashi, Y. Nakahara,
N. Hirai, H. Tsuchida, and D. Takaki,
Nissan Motor Co., Ltd., Application of
Low Pressure Cooled EGR System for
Downsizing Boosted Gasoline Engine,
JSAE Paper No. 20145306, May 2014.
6.0 CHARACTERIZATIONOFFRICTIONAND
OILCONSUMPTIONFORATWO-PIECE
OILCONTROLRING
Iijima, N., M. Susuda, Y. Iwata, M. Usui,
and K. Utashiro, Riken Corporation,
Effect of Peripheral Configuration of
Piston Rings for Friction Force and
Oil Consumption, JSAE Paper No.
20145343, May 2014.
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ENGINETECHNOLOGYPROGRESSINJAPAN
82
ARIGA TECHNOLOGIES, Bremerton, Washington, U.S.A. www.arigatech.com
Copyright 2014ARIGA TECHNOLOGIES
7.0 MEASUREMENTOFOILFILM
PRESSUREATTHEPISTONPINFOR
IMPROVEMENTOFSIMULATION
Yamakawa, N., K. Yamaguchi, K. Kobayashi,
and Y. Harayama, ART Metal, and
A. Ideo and Y. Mihara, Tokyo City
University, Measurement of Piston
Pin-Boss Contact Pressure Distribution
Using Thin-Film Sensor for a Gasoline
Engine,JSAE Paper No. 20145122,
May 2014.