Simulation and Optimization of DPF and SCR Systems · 2018. 12. 28. · Aftertreatment Simulation Strategy, II Integration BOOST 1D Aftertreatment CRUISE (using BOOST 1D as dll) BOOST

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Simulation andOptimization of DPF andSCR Systems

Roland WankerJohann C. Wurzenberger

CLEERS, Dearborn, May 2006 | Page 2

Contents

IntroductionModel Status

Model Integration

Model Application

Aftertreatment Simulation Workflow

Simulation ExamplesSCR System Optimization

DPF System Optimization

Summary

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Aftertreatment Simulation Strategy, I

Concepts for Emission Control SystemsDieselGasoline, ...

ComponentsCatalystsDPFsUrea/Diesel Injection, ...

Targets for OptimizationUniformity of Flow, ConcentrationsCompleteness of DPF RegenerationCycle EmissionsHeat-UpECU Calibration, ...

Variety in:

Integration of Models into a Variety of Simulation

Tools

Need for:

Pre-Defined Models

Ready-to Use Chemistry forCatalysts and DPFs

Flexibility of Models

to Define any Reaction ModelAccording to Customer Specific

Needs


Aftertreatment Simulation Strategy, IIIntegration

BOOST 1D Aftertreatment

CRUISE (using BOOST 1D as dll)

BOOST 1D s-function in Matlab/Simulink

FIRE 2D/3D

Identical physical and chemical models

ApplicationFlexibility

Diesel Oxidation Catalyst (DOC)

Diesel Particulate Filter (DPF, CSF)

Selective Catalytic Reduction (SCR)

Three Way CatalystDedicated kinetic models for each specific application

Use BOOST 1D Aftertreatment as Platform

User Coding Interface allows 100% Access to all FeaturesCustomer’s proprietary kinetic models

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BOOST 1D Aftertreatment1D, fast, robust

Pre-defined reaction models available

Connected to iSIGHT for parameter identification

Component and system level simulations andoptimization

Analysis of reaction chemistry

Prediction of mode emissions

Starting point for any aftertreatment simulation activity

Model Integration, I


FIRE 2D/3D Aftertreatment3D, very detailed

Pre-defined reaction models available

Pre-calibrated model from BOOST can be used

➨ Uniformity optimization(e.g. of species, temperature or mass flow)

➨ System optimization(e.g. spray, homogeneous reactions, DOC, SCR,DPF)

➨ CFD - FEM coupling(e.g. thermal stress during regeneration of a DPF)

Model Integration, II

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Model Integration, III

CRUISE AftertreatmentPre-calibrated model from BOOST can be used

➨ Investigate influence of different vehicles on catalystand DPF performance (and vice-versa)

Matlab/Simulink s-FunctionBOOST 1D aftertreatment connects to the wholeworld of MATLAB/SIMULINK


CatalystDOC (TWC): Heat-Up during Cold Start

DOC (TWC): Flow Distribution, and Mode Emissions

DOC: NO <--> NO2 Conversion

SCR: System Configuration (HSO, ...)

SCR: Injection of Urea, Evaporation and Mixing

DPF❧ Loading: Soot Distribution and Pressure Drop

❧ Regeneration: Duration, Completeness and ThermalStresses

Exhaust System❧ Losses to Ambient

❧ Heat-Up of Pipes, Insulation Material, ...

Application, Optimization Targets

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Contents


Model Integration

Model Application




Summary


Aftertreatment Workflow Concept

End

User-DefinedVariation

Parameter

Start

User-DefinedObjective

(i.e. based onexperimental

data)

Yes/No

Model

Solver

OptimizationTool

ParameterVariation

Post-ProcessorCheck Objective

Step 1:

Parameter Identification

VehicleComponent/

System LevelComponent/System Level

Step 2:

Optim

ization

Matlab/Simulink

Vehicle Simulation3D Simulation1D Simulation

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Comparison of Experimental Data with Guessed and Tuned Kinetic Parameters

DPF Regeneration100 BOOST Runs iniSIGHT v7.1

Oxi-cat Light-off840 BOOST Runs iniSIGHT v7.1

Step 1, Parameter Identification


Step 2, System Optimization

CRT-System,

30 NEDCs

DOC

DPFFlow

Heat Produced byBurning of Soot

Exhaust GasLineDOC and DPF

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Headline


Model Integration

Model Application




Summary


V-HSO System

Pre (Vor)-Catalyst

Hydrolysis, SCR and Oxidation Catalyst

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V-HSO System

Pre (Vor)-Catalyst

Hydrolysis, SCR and Oxidation CatalystSAE-2005-01-0948: (Wurzenberger and Wanker, AVL)

steady-state kinetic model validation

transient kinetic model validation

component level simulation

system level simulation

SAE-2006-01-0643: (Birkhold et al., BOSCH)

urea spray model validation

wallfilm model validation

evaporation and thermolysis reaction model validation


Rate Equations

Steady-State, Eley-Rideal Transient, Temkin-Type

Hydrolysis Section Hydrolysis Section

SCR Section SCR Section

Oxidation Section Oxidation Section

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HSO SCR Catalyst, Steady-Approach3 Different Reaction Sections

1 Hydrolysis Reaction for HCNO

3 SCR Reactions of Eley-Rideal Type

2 Oxidation Reactions for NH3

1 Reversible Oxidation Reaction for NO

HCNO

NH3 NOx

SCR, Pre-Defined Kinetic Models, “Steady”

SAE 2005-01-0948,Wurzenberger, Wanker


HSO SCR Catalyst, Transient Approach3 Different Reaction Sections

1 Hydrolysis Reaction for HCNO

2 Adsorption/Desorption Reactions for NH3

3 Transient SCR Reactions

2 Oxidation Reactions for NH3 (transient/steady)

1 Reversible Oxidation Reaction for NO

SCR, Pre-Defined Kinetic Models “Transient”

SAE 2005-01-0948, Wurzenberger, Wanker Catalysis Today (60), 2000, Nova et al.

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SCR, Pre-Oxidation Catalyst

SAE-2000-01-189, Gieshoff et.al, Degussa-Hüls AG

Light-Off for DifferentConverters Sizes

Light-Off, Comparisonwith Measurement


SCR, Light-Off Simulation

SAE-2000-01-188, Chandler et al., Johnson Matthey

Light-Off, Comparison with Measurement

SAE-2005-01-948, Wurzenberger and Wanker, AVL

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SCR, System Simulation, DOC and SCR

SAE-2000-01-188, Chandler et.al, Johnson Matthey

Light-Off for Different SCR and Pre-Catalyst Sizes


SCR, Urea Injection and 3D Flow

Urea Injection

Evaporation(Dukovicz Model)

Homogeneous GasPhase Reactions(Chemkin Interface)

HSO Converter Model,with Kinetic Parameterstuned in 1D

SAE-2005-01-948, Wurzenberger and Wanker, AVL

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SCR, 3D Species Distribution

H S O

HNCO, NH3, NO and NO2

NH3

NO

NO2NH3

HNCO


Contents


Model Integration

Model Application



DPF System OptimizationLoading

Parameter Identification

System Simulation

Summary

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xx

LL

00

xx LL

VV22 (x) (x)

VV11 (x) (x) VVww (x) (x)

2.0

1.5

0.0 0.2 0.4 0.6 0.8 1.0

V1 (x)V2 (x)

Vw (x)

VelocitiesVelocities

LLxx

Soot, Ash layer

00

Ws (x)

1.0

0.5

Sketch of a DPFSketch of a DPF

DPF Flow Model


DPF Model Features

Geometrysquare channelocto-square, ...

MaterialCordieriteSiCDura Trap AT,...

Soot Filtration ModelDepth FiltrationCake Filtration

Ash ModelRegeneration Model

Bare TrapCSFCatalytic Wall Reactions

SAE 2004-01-1132, Peters et al., AVL

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9.0 g/l

5 mm slices

Integration of pixels in all slices: 2D plot

Diesel Particulate FilterDPF Loading / Experiment

Computer Tomography


0 50 100 150 200 250length z – mm

0.00

0.06

0.08

0.10

0.12

0.14

0.02

0.04

Soo

t lay

er h

eigh

t –

mm

BOOST 4,5 g/l

BOOST 9 g/l

BOOST 0,25 g/l

Computer Tomography 9 g/l

Diesel Particulate FilterDPF Loading / Validation

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Comparison of Experimental Data With Guessed and Optimized KineticParameters

~100 1D Simulation Runs using iSIGHT v7.1

Diesel Particulate FilterRegeneration analysis: Parameter Identification


FIRE 3D: Diesel Exhaust Gas LineDPF Regeneration (post-injection)

Cat

DPF Flow

Heat Produced byBurning of Soot Heat Produced by

Oxidation of CO, HC,...

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Soot Mass Monolith Temperature

Wall Velocity O2 Mass Fraction

FIRE 3D: Diesel Exhaust Gas LineDPF Regeneration (post-injection)


DPF Regeneration(Movie)

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DPF Regeneration, Gas Temperature Front(Movie)


Conclusions and Outlook

Validated models for Catalysts and DPF available

DOC, TWC, SCR, ...

DPF, CSF, ...

Integrated Solution for Emissions ControlsSystem Optimization

1D: BOOST

2D/3D: FIRE

Vehicle: CRUISE

MATLAB Interface

Current activities

System level optimization

Integrate simulation into the development andapplication process

Documents

Simulation and Optimization of DPF and SCR Systems · 2018. 12. 28. · Aftertreatment Simulation Strategy, II Integration BOOST 1D Aftertreatment CRUISE (using BOOST 1D as dll) BOOST