Accuracy of diesel engine combustion metrics over the full range of engine operating conditions

Peter G. Dowell, Richard D. Burke, Sam Akehurst

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Measuring and analyzing combustion is a critical part of the development of high efficiency and low emitting engines. Faced with changes in legislation such as Real Driving Emissions and the fundamental change in the role of the combustion engine with the introduction of hybrid-electric powertrains, it is essential that combustion analysis can be conducted accurately across the full range of operating conditions. In this work, the sensitivity of five key combustion metrics is investigated with respect to eight necessary assumptions used for single zone Diesel Combustion analysis. The sensitivity was evaluated over the complete operating range of the engine using a combination of experimental and modelling techniques. This provides a holistic understanding of combustion measurement accuracy. For several metrics, it was found that the sensitivity at the mid speed/load condition was not representative of sensitivity across the full operating range, in particular at low speeds and loads. Peak heat release rate and indicated mean effective pressure were found to be most sensitive to the determination of top dead center (TDC) and the assumption of in-cylinder gas properties. An error of 0.5° in the location of TDC would cause on average a 4.2% error in peak heat release rate. The ratio of specific heats had a strong impact on peak heat release with an error of 8% for using the assumption of a constant value. A novel method for determining TDC was proposed which combined a filling and emptying simulation with measured data obtained experimentally from an advanced engine test rig with external boosting system. This approach improved the robustness of the prediction of TDC which will allow engineers to measure accurate combustion data in operating conditions representative of in-service applications.

Original languageEnglish
Title of host publicationEmissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development
PublisherAmerican Society of Mechanical Engineers (ASME)
Volume2
ISBN (Electronic)9780791851999
DOIs
Publication statusPublished - 1 Jan 2018
EventASME 2018 Internal Combustion Engine Division Fall Technical Conference, ICEF 2018 - San Diego, USA United States
Duration: 4 Nov 20187 Nov 2018

Conference

ConferenceASME 2018 Internal Combustion Engine Division Fall Technical Conference, ICEF 2018
CountryUSA United States
CitySan Diego
Period4/11/187/11/18

Keywords

  • Combustion Analysis
  • Diesel
  • Experimental diagnosis
  • Measurement Errors
  • Rate of Heat Release

ASJC Scopus subject areas

  • Automotive Engineering
  • Mechanical Engineering
  • Fuel Technology

Cite this

Dowell, P. G., Burke, R. D., & Akehurst, S. (2018). Accuracy of diesel engine combustion metrics over the full range of engine operating conditions. In Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development (Vol. 2). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/ICEF2018-9507

Accuracy of diesel engine combustion metrics over the full range of engine operating conditions. / Dowell, Peter G.; Burke, Richard D.; Akehurst, Sam.

Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development. Vol. 2 American Society of Mechanical Engineers (ASME), 2018.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Dowell, PG, Burke, RD & Akehurst, S 2018, Accuracy of diesel engine combustion metrics over the full range of engine operating conditions. in Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development. vol. 2, American Society of Mechanical Engineers (ASME), ASME 2018 Internal Combustion Engine Division Fall Technical Conference, ICEF 2018, San Diego, USA United States, 4/11/18. https://doi.org/10.1115/ICEF2018-9507
Dowell PG, Burke RD, Akehurst S. Accuracy of diesel engine combustion metrics over the full range of engine operating conditions. In Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development. Vol. 2. American Society of Mechanical Engineers (ASME). 2018 https://doi.org/10.1115/ICEF2018-9507
Dowell, Peter G. ; Burke, Richard D. ; Akehurst, Sam. / Accuracy of diesel engine combustion metrics over the full range of engine operating conditions. Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development. Vol. 2 American Society of Mechanical Engineers (ASME), 2018.
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