Multi-dimensional modeling of non-equilibrium plasma for automotive applications

Conference · Tue Apr 10 04:00:00 EDT 2018

DOI:https://doi.org/10.4271/2018-01-0198· OSTI ID:1501872

Scarcelli, Riccardo; Zhang, Anqi; Wallner, Thomas; Breden, Douglas; Karpatne, Anand; Raja, Laxminarayan; Ekoto, Isaac; Wolk, Benjamin

While spark-ignition (SI) engine technology is aggressively moving towards challenging (dilute and boosted) combustion regimes, advanced ignition technologies generating non-equilibrium types of plasma are being considered by the automotive industry as a potential replacement for the conventional spark-plug technology. However, there are currently no models that can describe the low-temperature plasma (LTP) ignition process in computational fluid dynamics (CFD) codes that are typically used in the multi-dimensional engine modeling community. A key question for the engine modelers that are trying to describe the non-equilibrium ignition physics concerns the plasma characteristics. A key challenge is also represented by the plasma formation timescale (nanoseconds) that can hardly be resolved within a full engine cycle simulation. This paper reports on the multi-dimensional modeling of LTP generated by a nanopulsed high-voltage discharge in a pin-to-pin electrode configuration, and evaluates the effects of ambient pressure on the post-discharge results. It is shown that a nanopulsed delivery can result in a LTP or a mode transition to an arc-like event depending on the mixture properties in the gap between the two electrodes. It is further shown that numerical predictions of the LTP-to-arc transition point as a function of ambient pressure along with qualitative distributions of important radicals and temperature closely match recent experiments with identical geometry and discharge characteristics. As a result, the high-fidelity modeling effort described in this paper can be used as a key tool to deliver in-depth understanding of non-equilibrium plasmas for automotive applications and lead to the future implementation of dedicated models for ignition technologies that are based on non-equilibrium plasma physics.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE) - Office of Vehicle Technology
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1501872
• Country of Publication: United States
• Language: English