This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Characterisation and Model Based Optimization of a Complete Diesel Engine/SCR System
Technical Paper
2009-01-0896
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
In order to make efficient use of a Diesel engine equipped with an SCR system, it's important to have a complete system approach when it comes to calibration of the engine and the aftertreatment system.
This paper presents a complete model of a heavy duty diesel engine equipped with a vanadia based SCR system. The diesel engine uses common rail fuel injection, a variable geometry turbocharger (VGT) and cooled EGR.
The engine model consists of a quasi steady gas exchange model combined with a two-zone zero dimensional combustion model. The combustion model is a predictive heat release model. Using the calculated zone temperatures, the corresponding NOx concentration is given by the original Zeldovich mechanism. The SCR catalyst model is of the state space type. The basic model structure is a series of continuously stirred tank reactors and the catalyst walls are discretized to describe mass transport inside the porous structure. Implicit methods are used to solve the ODEs which allow long time steps and high computational efficiency.
The combined engine-SCR model is a useful tool to characterize the system. A number of critical operating sequences are studied; step response from steady state low load conditions to high load and vice versa and also cold start experiments. Model based optimization is used aiming at achieving Euro VI emission levels while minimizing the brake specific fuel consumption (including Urea cost) by simultaneously optimizing the engine and SCR control parameters.
Topic
Citation
Ericson, C., Westerberg, B., Odenbrand, I., and Egnell, R., "Characterisation and Model Based Optimization of a Complete Diesel Engine/SCR System," SAE Technical Paper 2009-01-0896, 2009, https://doi.org/10.4271/2009-01-0896.Also In
References
- Bremm S. Kurze S. et al. “Bluetec Emission Control System for the US Tier 2 Bin 5 Legislation” SAE Technical papers 2008-01-1184 2008
- Ericson C. Andersson M. Egnell R. Westerberg B. “Modelling diesel engine combustion and NO x formation for model based control and simulation of engine and exhaust aftertreatment system” SAE Technical papers 2006-01-0687 2006
- Ericson C. Westerberg B. Odenbrand I. “A state-space simplified SCR catalyst model for real time applications” SAE Technical papers 2008-01-0616 2008
- Egnell R. “Combustion Diagnostics by Means of a Multizone Heat Release Analysis and NO Calculation” SAE Technical papers 981424 1998
- Andersson M. Johansson B. Hultqvist A. Noehre C. “A Predictive Real Time NOx Model for Conventional and Partially Premixed Combustion” SAE Technical papers 2006-01-3329 2006
- Chmela F. Engelmayer M. Pirker G. Wimmer M. “Prediction of Turbulence Controlled Combustion in Diesel Engines” Proceedings of THIESEL 2004 Conference on Thermo- and Fluid Dynamic Processes in Diesel Engines 2004
- Ericson C. “NO x Modelling of a Complete Diesel Engine/SCR System” Licentiate Thesis Division of Combustion Engines, Department of Energy Sciences, Lund Institute of Technology 2007
- Eriksson L. “Mean Value Models for Exhaust System Temperatures” SAE Technical Papers 2002-01-0374 2002
- Gill P.E. Murray W. Saunders M.A. “User's Guide for SNOPT Version 7: Software for Large-Scale Nonlinear Programming” 2007
- Gill P.E. Murray W. Saunders M.A. “SNOPT: An SQP algorithm for large-scale constrained optimization” SIAM Review 47 1 p. 99 131 2005
- Holmström K. Edvall M.M. Göran A.O. “TOMLAB – for Large-Scale Robust Optimization” Proceedings Nordic MATLAB Conference 2003 2003