Eaton EGR Pump Value Proposition - gtisoft.com › wp-content › uploads › 2019 › 11 › Eaton-EG… · © 2019 Eaton. All rights reserved.. Eaton EGR Pump Value Proposition

© 2019 Eaton. All rights reserved..

Eaton EGR Pump Value Proposition

Nilesh L. BagalNov. 4 2019

2© 2019 Eaton. All rights reserved..

Outline

• Background

• Base Model Development

• EGR Pump Analysis

• Air System changes

• Engine system optimization

• Summary


Background

• EGR Pump can be used to drive external EGR, enabling the use of a

fixed geometry turbine (FGT) in engines

• EGR pump enables decoupling of EGR from turbo which can drive

turbo matching for air system requirement

• The aim of this study is to understand the EGR Pump value

proposition for both EATON and engine/vehicle OEM’s

• This study is intended to help customers assess EGR pump viability

with current production hardware or new engine architectures


Diesel EGR PumpSaving fuel while meeting new emissions regulations

High-efficiency turbo Reduced engine pumping work Better fuel econ

Improved EGR and boost system

architecture: 1. Add EGR Pump to drive EGR

2. Delete EGR valve.

3. Optimize turbo for high-efficiency

boosting (replace VGT with FGT)

EGR Pump Value • Fuel economy

• Full-authority EGR rate control

• Deletion of some expensive

components


Analytical Evaluation of EGR Pump

• An analytical evaluation of the EGR pump value proposition is performed using a GT-POWER engine model. Key steps are:

• Base model development:

• Develop model representing current production HD diesel engine with VGT

• Calibrate and validate model using measured data

• Implement EGR pump and evaluate fuel benefits:

• Implement latest EGR pump configuration

• Assess fuel consumption improvement using optimized air system (FGT) and engine calibration

* Complete benefit evaluation

requires hardware testing


Base Model Development, Calibration and

Validation with Measured Data


Base Model Development

❖ Well calibrated and validated base model is the key

• Developed representative HD diesel engine model with VGT

• Model represents a state of the art current production HD diesel engine

• Engine: 13L, 6 cylinder, single stage VGT

• Model is calibrated to match SwRI CHEDE test data

• Close to production calibration data is used

• Performance data for 13 mode European Stationary Cycle (ESC) operating condition from SwRI

• Model is validated using with EGR sweep data


BTE & BSFC – Measured Data

BTE and BSFC values represent a efficient current production HD engine

BTE & BSFC – Measured Data


Base GT-POWER Engine Model

VGT

EGR Loop

Intake Exhaust

Cylinders


Model Result Comparison – Calibration Data

BTE (%) BSFC (g/kW-hr)

Model results compare well with lab data (< 3% max. error)

Measured Data

Mo

del R

esu

lt

Measured Data

Mo

del R

esu

lt


Model Result Comparison – Calibration Data

EGR (%) BNOx (g/kW-hr)

Model results compare well with lab data

Measured Data

Mo

del R

esu

lt

Measured Data

Mo

del R

esu

lt


1200 rpm Full Load 1800 rpm Full Load

Model results compare well with lab data

Crank Angle

Pre

ssu

re (

bar)

Pre

ssu

re (

bar)

Cylinder Pressure Comparison

Crank Angle


Evaluation of EGR Pump Fuel

Improvements using Engine Model


EGR Pump as EGR Driver System optimization

using EGR pump

Intercooler

EG

R C

oo

ler

Crank

PIntake

PExhaust

48V Power

1

3

24

EGR Pump

1. VG to FG turbine reduces pumping work

2. Exhaust design changes to improve

turbine efficiency

3. Combustion & Calibration optimization

4. Aftertreatment optimization

Pintake > Pexhaust

(pumping benefit)


Air System & Design Optimization

• Turbo matching is performed to provide required boost at peak torque and maintain low speed torque capability

• VGT Wastegate FGT

• Overall turbine efficiency improvement is predicted, moving from VGT (~ 69%) to optimized FGT (~ 75%) for A100 operating condition

• VGT Twin scroll FGT and split exhaust manifold

• Single log exhaust manifold is modified to split exhaust to account for high pulse energy

• Overall turbine efficiency improvement is predicted, moving from VGT (~ 69%) to optimized FGT (~ 87%) for A100 operating condition

• TVS 400cc EGR pump is implemented downstream of EGR cooler

• Engine out NOx levels are maintained


GT-POWER Engine Model with FGT

FGT

EGR Loop

Intake Exhaust

EGR Pump

Cylinders

Turbo Matching Object


Turbo Efficiency Comparison

❖ SwRI Data

• Single stage FGT GT45 turbo, split

exhaust manifold

Comp = 77%, Turb = 83%

❖ Eaton EGR Pump Analysis

• Single stage FGT with WG, open exhaust

manifold

Comp = 70%, Turb = 75%

• Twin scroll FGT with WG, split exhaust

manifold

Comp = 70%, Turb = 87%


BSFC % Improvement for 13 Mode ESC

1.8

3.4

3.1

3.5

1.7

2.5

2.7

4.34.6

3.6

2.4

2.40

1.2

0.6

0.5

0.4

1.2

1.5

2.4

2

1.7

0.7

0.7

Based on 13 Mode ESC Cycle Weightage, Model Predicts 1.15 and 3.1 % Fuel Benefit

Bubble size indicate

weightage at each mode

Bra

ke T

orq

ue (

N-m

)

Engine Speed (rpm)

Bra

ke T

orq

ue

(N

-m)

Engine Speed (rpm)


Engine System Optimization (CR, SOI,

EGR% and Miller Cycle)


Engine Optimization

• Evaluated engine calibration, Compression Ratio (CR) and Miller cycle sensitivity to further improve engine fuel efficiency for twin scroll architecture

• DOE’s were run for SOI, EGR%, CR and different LIVC cycles for all 12 modes

• Performance optimization:

• CR increased by 2

• IVC retarded by 30 crank deg.

• EGR and SOI optimized for each speed load operation

• Constraints:

• Meet base engine out BSNOx

• Peak cylinder pressure <250 bar


Engine Optimization


BSFC % Improvement

BSFC improvement up to 6.2 % is predicted.

Bra

ke T

orq

ue (

N-m

)

Engine Speed (rpm)

2.9

4.5

4.9

5.3

2.5

3.5

3.7

6.2

4.7

3.8

3.4

5.5


BTE Improvement

Base Optimized Engine with EGR Pump

Bra

ke T

orq

ue (

N-m

)

Engine Speed (rpm)

Bra

ke T

orq

ue (

N-m

)

45

45

43

39

45

44

43

38

44

43

41

36

45

44

42

37

46

46

44

40

47

45

44

39


Summary

• Well calibrated GT-POWER engine model is used to analytically evaluate

fuel consumption benefit of EGR pump.

• Two different turbo configurations (FGT and twin scroll) are evaluated by

replacing VGT to improve engine pumping losses.

• ~ 2.5% fuel consumption benefit predicted when converting from VGT to

FGT with EGR pump.

• ~ 5% fuel consumption benefit predicted when converting from VGT to twin

scroll FGT with EGR pump.


Summary

• Engine system and calibration optimization is performed.

• Optimized engine with EGR pump, single stage twin scroll FGT with

wastegate and split exhaust manifold design model predicts up to 6.2% fuel

consumption benefit.

• Based on drive cycle weighting, model predicts 1 – 4 % fuel benefit for 13

mode ESC engine dyno cycle.

• GT-POWER is a good tool to analytically evaluate performance. GT example

models provide a good representative base model.


Acknowledgement

• Southwest Research Institute (SwRI)

• Gamma Technologies


Documents

Eaton EGR Pump Value Proposition - gtisoft.com › wp-content › uploads › 2019 › 11 › Eaton-EG… · © 2019 Eaton. All rights reserved.. Eaton EGR Pump Value Proposition