light-duty diesel light duty diesel fuel injection systems

CRC Advanced Fuel and Engine Efficiency Workshop

Light-Duty DieselLight Duty Diesel Fuel Injection Systems


DS/ENS1-NA | 2/14/2014 | ENS_1481_018 | © 2014 Robert Bosch LLC and affiliates. All rights reserved.

Diesel Systems

Feb. 2014

1


New Powertrains: Estimated world market volumes

113

94 EV HEV

PHEV3.1

EV2.5

HEV/PHEV

1.7

EV0.181

94HEV/PHEV

2.7

0.7HEV6.5

EVElectric vehicle

79.490.8

101.1PHEVPlug-in hybrid

HEVHybrid vehicle

Pure ICEInternal combustion engine

Sales PC & LCV<6t (millions of vehicles)

2012 2015 2020


Diesel Systems

Internal Combustion Engines will remain the predominant powertrain for the near future

2


U.S. Passenger Car / Light-Duty Emissions Evolution

0.12

0.14

- 95%

0.08

0.10

g/m

i]

- 95%

Bin 10

- 88% - 90%

- 88%

Tier 1

Tier 2

0.04

0.06

PM [g

Bin 9

Bin 10

2006 vehicles1999 vehicles

- 88%

Bin 80.00

0.02Bin 8Bin 5 Bin 8Bin 8Bin 8Bin 8Bin 8

0.01Bin 8Bin 8

NOx [g/mi]

0 0.2 0.4 0.6 0.80.07 1.2 1.4Bin 2

Current Clean Diesel VehiclesBin 2Bin 2


Diesel Systems

More than 90% Reduction in Criteria Emissions in 10 Years

3


Optimizing the Diesel System: Total System Approach

Powertrain

Air Management

Combustion Process

Reduction of compression ratio

Hybrid Technology

Swirl-/Throttle Valve

Turbo Charger/VGT*

Combustion strategies

Exhaust gas management

Fast Catalyst Light-Off (reduce thermal losses)

Diesel Particulate FilterFuel Injection System Tolerance Reduction

Diesel Particulate Filter

NOx storage catalyst

Catalyst temp control

New Generations Multiple Injections Reduced Tolerance Optimized Nozzle

Zero Fuel Calibration Fuel Balancing Control

Individual Cylinder Control


Diesel Systems

Optimized Nozzle Control*VGT= Variable Geometry Turbo

4


Injection strategy – Multiple Events per Combustion Cycle

High -pressure cycle

sure

[bar

] 150

100Cylinder pressure

ylin

der p

ress

-180 0 180[ °CA ]

50

0

Cy 80 180[ CA ]

Precise control of

Exhaust-gas aftertreatment-

< 1mm3 3 ... 60mm3< 1mm3 � 1...3mm3 � 5...30mm3

injected fuel quantity

Verbrennungs-

optimierungAkustik-

maßnahmen

Acoustic-measures

Optimisation of combustion

gmanagement

Resultant system impact


Diesel Systems

5


Fuel System CharacteristicsHistorical Trend of Fuel Injection Pressures Influence of injection pressure and EGR rate

Specific Fuel Consumption

Required pressure level depends on:• Desired power output

E i i d/ CO

Increasing Pressure, EGR rate

Consumption• Emission- and/or CO2-reduction potential

Source: 5th Intern. Exhaust Gas and Particulate Emission Forum 2008, MAN AG

Smoke number

Injection Rate Shape


Diesel Systems

Emissions Requirements Drive Need for Fuel System Flexibility

6


Advanced Injection Strategies: Multiple Injections

1

Influence of injection strategy onfuel consumption and smoke

Influence of injection strategy on smoke and noise

Single Cylinder Research EngineSwept Vol.:≈ 540 cm³; 2000 rpm; 8 bar IMEP; Noise ≈ const.

Single Cylinder Testing0.5l/cyl, 2000 rpm, IMEP=8bar

0.7

0.8

0.9

1

Previous Focus

0.4

0.5

0.6

0.7

Soo

t [g/

kg] Conventional Injection

Strategy(1 or 2 x PI)

0 1

0.2

0.3

0.4S

Digital Rate Shaping I( 1 or 2 x ClosePI)

Digital Rate Shaping II(PI or ClosePI +

0.1 g/kg

0

0.1

80 82 84 86 88 90 92Noise [dB]

POI as Needed)New Focus

2 dB PI = Pilot InjectionPOI = Post Injection


Diesel Systems

Benefits of new injection patterns being evaluated

7


Hydrocarbon Emissions: Minimized HC-Volume


Diesel Systems

Minimized nozzle HC-volume results in significant HC-reduction potential

8


Advanced Fuel System Strategies: Control Algorithms Emissions and performance requirements are placing additional demands on fuel system

Fueling Accuracy Improved System Control Drift and Temperature Compensation Drift and Temperature Compensation

Example Corrective Functions for Improved System Behavior

Valve Closing Detection and Injector Temperature

Compensation

Fuel Balancing Control by Delta Rail Pressure

Quantity Wave Correction Adaptive Metering Unit and Pressure Control Valve Control

Compensation

Measure valve closing delay inorder to compensate for fuelviscosity as well as injector drift

Measures cylinder specificrail pressure drop caused by eachinjection and adjusts deviation

Reduces fuelling error caused bypressure oscillations in systemdue to injection pattern

Correction of controller deviationfor improved rail pressure control


Diesel Systems

Advanced Control Algorithms Available to Support System Requirements

9


Advanced Fuel System Strategies: Fuel Quality Fuel quality and variation affects system performance

Functionality of system Exhaust emissions Performance requirements Performance requirements

Fuel Quality Detection by Engine Speed Component Robustness Measures

Example Countermeasures to Compensate for Fuel Effects

• Detection of fuel quality variation based on engine speed roughness

• Compensation of effectsfrom fuel quality variation

• Material choices• Material choices

• Design choices


Diesel Systems

Components and System Functions Available to Provide Limited Compensation for Fuel Quality

10


Fuel Quality effects on fuel system componentsFuel Quality effects on fuel system components

Environmental effects Cleanliness particle erosive wear

Fuel Quality variation effects Low Lubricity premature wear

spray hole pump polygon Pump tappetspray hole pump polygon Pump tappet

Water content corrosion Low Oxidation Stability deposit formation

valve bodypump

DRV

Contaminants deposits (e.g. soap type) Kinematic Viscosity fuel metering

valve piston

DRV

Cetane Number sub-optimal combustion

valve piston


Diesel Systems

Consistent world-class Diesel fuel quality enables optimum performance and durability

11


SummarySummary The internal combustion engine will remain the dominant transportation

engine for decades

Diesel performance and exhaust emission targets are achievable and require total engine control system integration

Advanced fuel injection systems and control techniques discussed for optimization of the combustion event: Injection rate shapingj p g Nozzle design Control algorithms

While some control techniques provide limited compensation for fuel quality variation; consistent state-of-the-art Diesel fuel quality assures vehicle performance and durability expectations are met


Diesel Systems

12

light-duty diesel light duty diesel fuel injection systems

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