Abstract
This article presents the results of computational studies investigating the ignition of high-pressure natural gas jets in a compression-ignition engine with glow plug ignition assist. The simulation was conducted using a KIVA-3V-based three-dimensional engine model, along with an improved fuel injector model, a detailed cut-off glow plug shield model and a modified two-step methane reaction mechanism, to simulate the natural gas injection and ignition. The simulated results demonstrate the significance of using a shield for the glow plug. Compared to an unshielded (bare) glow plug, the shield not only reduces the heat loss from the hot glow plug surface to the cold intake air charge and the cold injected gas jet but also traps the fuel mixture to increase its residence time adjacent to the hot surface. Over a representative range of heavy-duty diesel engine operating conditions, a shielded glow plug greatly improves the natural gas engine performance and provides reliable ignition, while an unshielded glow plug can only be optimized for specific conditions. The understanding of glow plug shield behavior gained from the simulations suggests avenues for improved shield designs that would yield further reduced ignition delays.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.