Modeling Nanosecond-Pulsed Spark Discharge and Flame Kernel Evolution
- Argonne National Lab. (ANL), Lemont, IL (United States)
- Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Dilute combustion, either using exhaust gas recirculation or with excess air, is considered a promising strategy to improve the thermal efficiency of internal combustion engines. However, the dilute air-fuel mixture, especially under intensified turbulence and high-pressure conditions, poses significant challenges for ignitability and combustion stability, which may limit the attainable efficiency benefits. In-depth knowledge of the flame kernel evolution to stabilize ignition and combustion in a challenging environment is crucial for effective engine development and optimization. To date, a comprehensive understanding of ignition processes that result in the development of fully predictive ignition models usable by the automotive industry does not yet exist. Spark-ignition consists of a wide range of physics that includes electrical discharge, plasma evolution, joule-heating of gas, and flame kernel initiation and growth into a self-sustainable flame. In this study, an advanced approach is proposed to model spark-ignition energy deposition and flame kernel growth. To decouple the flame kernel growth from the electrical discharge, a nanosecond-pulsed high-voltage discharge is used to trigger spark-ignition in an optically accessible small ignition test vessel with a quiescent mixture of air and methane. Initial conditions for the flame kernel, including its thermodynamic state and species composition, are derived from a plasma-chemical equilibrium calculation. The geometric shape and dimension of the kernel are characterized using a multi-dimensional thermal plasma solver. Here, the proposed modeling approach is evaluated using a high-fidelity computational fluid dynamics procedure to compare the simulated flame kernel evolution against flame boundaries from companion Schlieren images.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Vehicle Technologies Office
- Grant/Contract Number:
- AC02-06CH11357
- OSTI ID:
- 1840600
- Journal Information:
- Journal of Energy Resources Technology, Vol. 144, Issue 2; ISSN 0195-0738
- Publisher:
- ASMECopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Numerical Investigation of Spark Ignition Events in Lean and Dilute Methane/Air Mixtures using a Detailed Energy Deposition Model
Flow field effects on flame kernel formation in a spark-ignition engine