INDICATING AND COMBUSTION DEVELOPMENT TOOLS September 2009 Alfred Kristoferitsch Business Development Manager AVL List, Graz/Austria
INDICATING AND COMBUSTION DEVELOPMENT TOOLS
CONTENT: The Indicating Measuring Chain Basics of Indicating and Parameters Indicating for Emission Reduction Contribution of Optical Measurement Tools AVL Combustion Measurement - Product overview Application Examples
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INDICATING AND COMBUSTION ANALYSIS How we notice combustion ? Amplifier
High Speed Data Acquisition
• Charge Amplifier
• Indicating System
Crank Angle Signal
Data Acquisition SW
• Crank Angle Encoder
• Control of HW • Calculation / Analysis
Cylinder Pressure
Post Data Processing
• High Pressure Sensor (piezo electric)
• Post Data Processing Tool
Meaningful Measurement Results require … accurate Measurement tools 3
INDICATING AND COMBUSTION ANALYSIS How we notice combustion ? Typical measurements
Cylinder pressure
Degree Crank Angle – crank angle encoder / calculator
Low Pressure measurement in intake and exhaust manifold
Line Pressure Sensors (max. 3000 bar)
TDC Sensor - Top dead center sensor
Turbo Speed Sensor
Needle Lift Sensor / Valve Lift Sensor
Ignition / Injection Timing
... 4
STANDARD EVALUATION OF THE CYLINDER PRESSURE Indicating parameters
bar
• IMEP – Indicated Mean Effective Pressure
Pmax
• Maximum Pressure; pmax
20 dp/dα
• Angle of Maximum Pressure
10
• Maximum Pressure Rise • 50% Heat Release Angle
0
• Start and End of Combustion
αpmax
• Cyclic Variation of Above Values (statistics)
α dp/dα
-15
+15
deg CA
• Cylinder Distribution of Above Values (statistics)
Pressure measurement for thermodynamic analysis: power, heat, energy balance MI DH 96IX5E-23
STANDARD EVALUATION OF THE CYLINDER PRESSURE
Cylinder pressure
50
bar 1000 800
40
600
30
Injection line pressure
20
400 200 mm 1.0
10 0 Nozzle needle lift
0.5 0
-60
-45
-30
-15
0
15
30
45
Line pressure
Combustion chamber pressure
Needle lift
bar
60
deg CA MI DH 96IX6E-21
Mass fraction burnt - %
Measurement / Calculation Values kJ/m3 grd deg
Rate of hea t release -
THERMODYNAMIC RESULT VALUES
Result Values
50
Center of gravity of combustion 0
α GQ
ααGQ GQ
100% Angle of Integral Heat
50%
α 5% StStart of combustion α 50% Main burning activity
0%
α 95% End of combustion α 5
α 50%
0 TDC
α 95%
deg CA
α MI DH 96IX 7 E-27
Cylinder pressure
STATISTICAL EVALUATION OF CYLINDER PRESSURE SIGNALS 40 bar 30
Measurement
20 10 0 -60
0
60 deg CA
120
180 α
Result values 3,4 bar 3,0 20 deg CA 0
IMEP
αmax
IMEP
0
Statistics
Maximum
pim a x
pi
Meanvalue
piM e a n
Minimum
pim i n
Coefficient of variance
Vp i
pim a x piM e a n pim i n
20
40 60 Cycle
80
100
MI DH 96IX 8 E-28
ENGINE DEVELOPMENT CYCLE
pre- series
steps in development
certification endurance test test bed and vehicle calibration on vehicle development and calibration on test bed research 0
50
100
% Time MI FM 98IX9E-24
LINK BETWEEN COMBUSTION AND EMISSION • misfiring
HC
• knock
NOx
• steep temp / pressure rise
NOx
• too early combustion
NOx
• too late combustion
HC, PM, soot
• partial combustion (wall film, condensation/cold components, over fueling, fat mixture, improper spray / geometry, … )
HC, PM, soot
NOx
temp reduction - EGR
PM, soot
premixed flame
HC
no unburnt fuel, stable combustion 10
INFLUENCE OF COMBUSTION ON EMISSIONS
soft combustion Rate of Heat Release -100
- low NOx
stiff combustion - high NOx
- low noise
- high noise
- increased soot - high HC
-80
-60
-40
-20
0
20
40
60
80
100
11
COMBUSTION TIMING AND EMISSIONS %
260
α HC
220
Emission
180
SOI = NOX
start of injection
140 100 60
deg CA - 4
-3 -2 advanced
-1
0
1
lowest SFC
2
3 4 retarded
5
6 12
INFLUENCE OF INJECTION PARAMETERS
NOX
HC
PM
Power/ Torque
Noise
Appl. Effort
High Injection Pressure Late Start of Injection Pilot Injection Injection Rate Control Nozzle Hole Quality Post Injection
Positive Effect
Negative Effect 13
INDICATING AND COMBUSTION ANALYSIS How we notice combustion ?
Limitation of Information derived from Combustion Pressure •
Flame quality – can not be evaluated
•
emissions are directly linked to flame quality
Flame quality can be studied in detail with optical methods giving a deeper understanding of the actual combustion Optical methods are grown up – they are no longer a scientific tool for R&D only •
tailored test bed solutions for typical problems are available
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INDICATING AND COMBUSTION DEVELOPMENT TOOLS - VISIOSCOPE VISIOSCOPE
live pictures with full geometry information or temperature information only one picture per cycle
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INDICATING AND COMBUSTION DEVELOPMENT TOOLS - VISIOLUTION VISIOLUTION advantage: good information over entire cylinder cross section with highest CA resolution disadvantage: lower spatial resolution 14%
up to 40 channels 8%
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INDICATING AND COMBUSTION DEVELOPMENT TOOLS - VISIOSET VISIOSET advantage: rough information over entire cylinder cross section and good information on flame around spark plug with highest CA resolution disadvantage: lowest spatial resolution -60 °CA 140
up to 8 channels
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OPTICAL MEASUREMENTS – FLAME OKAY
Stoichiometric, premixed flame in warm engine: all fuel evaporated and mixed with air
Flame radiation is synchronous with combustion pressure
Stationary part load, benchmark example Flame radiation
Exhaust
speed
Inlet
-180
-90
0
90
180
270
VisoFlame Spark Plug Probe 18
OPTICAL MEASUREMENTS – SOOTING FLAME
Premixed flame starts at spark plug and ignites wet surfaces fuel
Premixed flame radiation, then ongoing surface diffusion flame radiation
Early starting cycle in cold engine
-180
Premixed flame not seen in photograph because of low intensity flame radiation. Very bright diffusion flame
-90
0
90
180
270
Premixed flame burning volume charge yields combustion pressure
Photograph by Witze, Green,Sandia 19
INDICATING AND COMBUSTION DEVELOPMENT TOOL - COLDSTART Mixture conditions at cold start. Schematic by Toyota, SAE 950074
Ignition: little fuel vapor near spark plug causes small flame
Premixed combustion: pressure rise as volume charge burns Liquid film combustion: very bright flame, but low rate of heat release
-180
-90
0
90
180
270
Ignition phase disturbed by overfuelliing, fuel droplets hitting the flame kernel 20
INDICATING AND COMBUSTION DEVELOPMENT TOOLS - VISIOFEM VISIOFEM advantage: cheapest optical system excellent for transient soot measurements disadvantage: 20 IMEP 15 bar
only one conical segment can be viewed
IMEP visio-soot
10
2 channels 5 opacity 0 0
100
200
300 21
VISIOFEM
optical amplifier
Urgent statement of a leading diesel car producer:
fibre optics „Our600nm CR injection systems operated in stationary engine tests cable 950nm we manage to optimise for low soot and NOx. But we do not understand how to optimise CR in transient mode!
How much pilot, pre- main- post injection ? How many crank angle degrees in between ? How do we adapt to changing load, boost pressure, residual gas ?
optical sensor in glow plug adapter
We need a real time, crank angle resolved transient data acquisition for soot and NOx.“
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HOW TO READ THE DATA? ... we get traces of - injection - cylinder pressure - flame intensity
= f (EOI) flame intensity amount of soot two-colour flame evaluation temperature / NOx
IMEP: 5 bar FSN
0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0
trend verification with Filter Smoke Number (FSN)
-15
-10
-5
0
0.25 0.2 0.15 0.1 0.05
5
D_VFEM - rel. units
figure of merit
EOI
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CONCLUSION – COMBUSTION MEASUREMENT
combustion analysis with pressure transducers is a very powerful tool for engine improvement with some simple algorithm the trend in emissions, noise or fuel consumption can be easily assessed before going to detailed emission analysis the extend of improvement can be already assessed also by means of optical measurement tools
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AVL COMBUSTION MEASUREMENT Product Overview Alfred Kristoferitsch Combustion Measurement AVL Graz
Product Overview
Post Data Processing AVL CONCERTO
Indicating Systems System Overview IndiCom
Amplifier Charge Amplifier Amplifier with more functions
Sensors Pressure Sensors Crank Angle Encoder 26
SENSORS Combustion Pressure – AVL GaPO4
High thermal stability: temperature consistent up to 970°C no twin growth (compared to quartz)
High piezoelectric sensitivity: high sensitivity in small sensors as well (GU21C 35pC/bar) excellent distance between signal and noise
No thermal sensitivity change
assumption for correct measuring results under all load point (typical sensitivity change for AVL GU12P between 20°C - 400°C : +0,5% / -0,2%) 27
SENSORS Combustion Pressure AVL - GaPO4 Direct mounted preferred solution for highest accuracy ideal mounting position possible
Spark Plug no additional bore in cylinder head required wide range customer spark plugs available sensor is as close as possible to the combustion chamber – high accuracy / no pipe oscillation
Glow plug no additional bore in cylinder head required sensor is as close as possible to the combustion chamber – high accuracy / no pipe oscillation 28
SENSORS Crank angle based measurement – optical sensor AVL Chrank Angle Encoder 365C standard combustion engines optical measurement principle for mounting a free shaft end or belt pulley is required
AVL Chrank Angle Encoder 365X open disc used for mounting situations without free shaft end, e.g. on drive side
AVL Chrank Angle Encoder 365R designed for racing application
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SENSORS Further sensors available:
Low Pressure Sensor Pressure measurement in Intake and exhaust manifold
Line Pressure Sensors up to 3000 bar line pressure TDC Sensor Top dead center sensor
Turbo Speed Sensor Laser sensor Needle Lift Sensor Valve Lift Sensor
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AVL Amplifier Product Portfolio MicroIFEM MicroIFEM - 4 Channel amplifier 4 Ch. Piezo 4 Ch. Multi Purpose (MP) 2 Ch. Piezo / 2 Ch. MP
FlexIFEM FlexIFEM – 1/2 Channel amplifier 1/2 Ch. Piezo MP available 2010
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FLEXIFEM – MORE VALUE LCD Display Visualizes operation menu User-friendly setting of parameters Displays results or pressure curve Calculation Provides cycle by cycle calculations Peak cylinder pressure pmax Engine speed Output of warning and alarm levels FlexIFEM Advanced Combustion Noise function Knocking (not yet available)
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FLEXIFEM Advanced – Combustion Noise Meter
Stand alone charge amplifier with integrated combustion noise function Comparability to Analog AVL 4050 Combustion noise meter AVL combustion noise function in IndiCom
Download your own transfer (MFFR) curve Updates via software Further algorithms planned : e.g. AVL CKI
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AVL INDICATING SYSTEMS LIGHT LINE
NEW IndiSmart
IndiModul Start
Including Charge Amplifier
• Cost-Effective Solution for Standard Indicating applications • Light System with full upgradeability to Advanced Indicating System • Ideal for combustion investigation on 4-6 cylinder engines • Easy-to-use IndiCom Light Interface • 0.1 deg. CA measurement resolution up to 11000 rpm with max. 1530 measuring points per cycle • IEEE1394 Firewire interface 34
INDICOM LIGHT SOFTWARE
Graphical User Interface: very easy to use workflow oriented architecture built-in plausibility control fast and seamless PUMA integration wide range of standard calculations extension packages for Diesel and Gasoline engines AVL Sensor Data Management SDM
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LIGHT LINE SPECIALS – UNIVERSITY PACKAGE Development package IndiModul Start (8 channels) IndiCom Advanced Coldstart Knock Analysis Noise Analysis 1x Micro IFEM (Piezo or Multipurpose) 365C Crank Angle Encoder 2x uncooled Piezo-Tansducers with mounting tools Concerto with 5 NW licenses Care Support (2 years without SW subscription) 36
AVL INDICATING SYSTEMS Advanced Line
IndiModul
IndiSet
IndiMaster
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DATA POSTPROCESSING WITH AVL CONCERTO
Detailed analysis of the indicating data (IFile) in the office Investigation of the correlation between combustion values and testbed results Sophisticated diagrams and graphical objects for clear result presentation Advanced calculation library, easy to use with CalcGraf and Formula Editor Automated data processing with scripting
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GCA Geometry of cylinder and ports (customer) coeffs of discharge (customer) 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1
0
0
0.1
0.2
0.3
0.4
0.5
Valve lift (customer) Pintake, Tintake pcylinder
Adjustment using pressure Filter, Adjustment and Combustion Analysis
18 0
0 6 9 0
pexhaust, Texhaust
Adjustment using pressure 39
Indicating
Together at the Test Bed
short loop between simulation and measurement
Application of Simulation Tools at the Test Rig
Indication and Simulation Together
1-d Thermodynamic Simulation 40
AVL VISIOSCOPE - SYSTEM OVERVIEW Camera Endoscope
PC
Fibre
Illumination Unit
Optic Light Guide
Crank Angle Signal 41
AVL VISIOSCOPE - OPTICAL ACCESS
67 °
object object
rod lenses with cooling channel
67 °
cooled endoscope
cooling ducts
ø 4 or 7mm cameraconnection
Objective lens
rod lenses ø 8mm
rod lenses with integrated fibres uncooled endoscopes Light entrance
straight forward view
viewing direction
0°
oblique view
30°
oblique view
70° 42
AVL VISIOSCOPE - RECORDING TECHNIQUE
-8,5°
Crank Angle -6,5° -4.5° -2.5°
-0.5°
Repetitions
1
2
3
4
5 n
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Example Visioscope Diesel Flame
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Example Visioscope Diesel Flame / Flame Temperature
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Example Visioscope DI Gasoline
46
Example Visioscope Gasoline Wall Wetting
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THANK YOU FOR YOUR ATTENTION
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