Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine

With emissions regulations becoming increasingly restrictive and the advent of real driving emissions limits, control of engine-out NOx emissions remains an important research topic for diesel engines. Progress in experimental engine development and computational modelling has led to the generation...

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Main Authors: Bajwa, A, Zou, G, Zhong, F, Fang, X, Leach, F, Davy, M
Format: Journal article
Language:English
Published: SAGE Publications 2024
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author Bajwa, A
Zou, G
Zhong, F
Fang, X
Leach, F
Davy, M
author_facet Bajwa, A
Zou, G
Zhong, F
Fang, X
Leach, F
Davy, M
author_sort Bajwa, A
collection OXFORD
description With emissions regulations becoming increasingly restrictive and the advent of real driving emissions limits, control of engine-out NOx emissions remains an important research topic for diesel engines. Progress in experimental engine development and computational modelling has led to the generation of a large amount of high-fidelity emissions and in-cylinder data, making it attractive to use data-driven emissions prediction and control models. While pure datadriven methods have shown robustness in NOx prediction during steady-state engine operation, deficiencies are found under transient operation and at engine conditions far outside the training range. Therefore, physics-based, mean value models that capture cyclic-level changes in in-cylinder thermo-chemical properties appear as an attractive option for transient NOx emissions modelling. Previous experimental studies have highlighted the existence of a very strong correlation between peak cylinder pressure and cyclic NOx emissions. In this study, a cyclic peak pressure-based semi-empirical NOx prediction model is developed. The model is calibrated using high-speed NO and NO2 emissions measurements during transient engine operation and then tested under different transient operating conditions. The transient performance of the physical model is compared to that of a previously developed data-driven (artificial neural network) model, and is found to be superior, with a better dynamic response and low (<10%) errors. The results shown in this study are encouraging for the use of such models as virtual sensors for real-time emissions monitoring and as complimentary models for future physics-guided neural network development.
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spelling oxford-uuid:ced1b1aa-89a9-44c5-8a74-2d96c83dd9d32024-12-19T08:58:39ZDevelopment of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engineJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:ced1b1aa-89a9-44c5-8a74-2d96c83dd9d3EnglishSymplectic ElementsSAGE Publications2024Bajwa, AZou, GZhong, FFang, XLeach, FDavy, MWith emissions regulations becoming increasingly restrictive and the advent of real driving emissions limits, control of engine-out NOx emissions remains an important research topic for diesel engines. Progress in experimental engine development and computational modelling has led to the generation of a large amount of high-fidelity emissions and in-cylinder data, making it attractive to use data-driven emissions prediction and control models. While pure datadriven methods have shown robustness in NOx prediction during steady-state engine operation, deficiencies are found under transient operation and at engine conditions far outside the training range. Therefore, physics-based, mean value models that capture cyclic-level changes in in-cylinder thermo-chemical properties appear as an attractive option for transient NOx emissions modelling. Previous experimental studies have highlighted the existence of a very strong correlation between peak cylinder pressure and cyclic NOx emissions. In this study, a cyclic peak pressure-based semi-empirical NOx prediction model is developed. The model is calibrated using high-speed NO and NO2 emissions measurements during transient engine operation and then tested under different transient operating conditions. The transient performance of the physical model is compared to that of a previously developed data-driven (artificial neural network) model, and is found to be superior, with a better dynamic response and low (<10%) errors. The results shown in this study are encouraging for the use of such models as virtual sensors for real-time emissions monitoring and as complimentary models for future physics-guided neural network development.
spellingShingle Bajwa, A
Zou, G
Zhong, F
Fang, X
Leach, F
Davy, M
Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title_full Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title_fullStr Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title_full_unstemmed Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title_short Development of a semi-empirical physical model for transient NOx emissions prediction from a high-speed diesel engine
title_sort development of a semi empirical physical model for transient nox emissions prediction from a high speed diesel engine
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