Modeling study of reactive species formation from C1–C3 alkanes in an HCCI engine
Authors: Ahmad Saylam, Burak Atakan, and Sebastian A. Kaiser
Document type: Published journal article
Journal: Combustion Theory and Modelling
Publication details: Volume 23, Issue 6, pages 1119–1133, 2019
Published online:
Access and rights note: This page provides bibliographic information and an independently written technical summary. No publisher Version of Record or other full-text copy is hosted on this website.
Independent technical summary
The study uses a single-zone homogeneous charge compression ignition model to examine selective formation of reactive intermediates during lean oxidation of methane, ethane and propane.
The analysis varies compression ratio, engine speed, equivalence ratio, intake temperature and selected reactive additions to identify operating conditions that favour oxygenated hydrocarbons, hydrogen peroxide and ethylene before transition to high-temperature autoignition.
A near-optimal operating region was reported for an intake temperature of 400 K and intake pressure of 1 bar, with compression ratios of approximately 9–13, an engine speed of 400 rpm and lean equivalence ratios of approximately 0.05–0.25. The useful window was especially narrow with respect to compression ratio.
Under the reported optimum conditions, the model predicted conversion of part of the methane feed to formaldehyde and hydrogen peroxide, while ethane and propane produced ethylene. The work therefore explores HCCI operation not only as a combustion mode but also as a possible low-temperature partial-oxidation reactor for producing chemically useful intermediates.
Technical contribution
The paper defines an operating-window concept for intermediate-species production within an engine-like compression cycle. It links detailed low- and intermediate-temperature alkane chemistry to controllable engine parameters and evaluates the possibility of integrating fuel conversion, reactive-species generation and combustion-system stabilization.
The work is also relevant to broader polygeneration concepts in which a reciprocating engine or compression reactor is considered as a flexible chemical-conversion device rather than solely as a source of mechanical work.
Scope and application boundary
The results are based on single-zone modelling. Such a model does not resolve spatial temperature gradients, wall heat transfer, boundary layers, crevice zones, mixing non-uniformity, detailed fluid mechanics, cycle-to-cycle variation or product extraction.
The reported yields and operating windows should therefore be treated as modelling evidence and process hypotheses rather than validated reactor performance. Experimental confirmation requires controlled engine or compression-reactor studies with time-resolved temperature, pressure and species measurements.
Practical development would additionally require assessment of product quenching and recovery, material compatibility, safety, separation energy, conversion efficiency, by-products, emissions, cycle stability and comparison with conventional chemical-production routes.
Publisher access
The Version of Record is available from Taylor & Francis through the DOI: access the publisher record . Access may require an institutional or individual subscription.
Citation
Saylam, A., Atakan, B., & Kaiser, S. A. (2019). Modeling study of reactive species formation from C1–C3 alkanes in an HCCI engine. Combustion Theory and Modelling, 23(6), 1119–1133. https://doi.org/10.1080/13647830.2019.1638972
Related technical resources
- Degree Centrality of Combustion Reaction Networks for Analysing and Modelling Combustion Processes
- HCCI Engine as Chemical Reactor to Produce Fuel/Chemicals
- Reduction of Large Detailed Chemical Kinetic Mechanisms for Autoignition Using Joint Analyses of Reaction Rates and Sensitivities
- Doctoral Thesis on Hydrocarbon Oxidation, Autoignition and Mechanism Reduction