Predicting Cycle-to-cycle Variations in a Spark-ignition Engine using Multi-cycle Large Eddy Simulation

Conference · Mon Mar 25 00:00:00 EDT 2019

OSTI ID:1513503

Su, Yunde ^[1]; Splitter, Derek ^[2]; Kim, Seung Hyun ^[3]

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1. The Ohio State Univ., Columbus, OH (United States); The Ohio State University
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. The Ohio State Univ., Columbus, OH (United States)

Multi-cycle large eddy simulation (LES) of a spark-ignition engine has been performed to predict cycle-to-cycle variations (CCV). To describe spark-ignited premixed flame propagation, the front propagation formulation (FPF) method is combined with a laminar-to-turbulent flame transition model that describes the non-equilibrium flame development processes during the initial stage of the kernel growth. In the laminar-to-turbulent flame transition model, the effects of turbulence on the variations in the laminar-to-turbulent flame transition time are modeled based on the Kolmogorov energy cascade. 15 consecutive cycle LES of in-cylinder processes in a spark-ignition four-valve single cylinder engine is conducted. The predicted in-cylinder pressure is compared with the experimental measurements. The range of CCV observed in the experiment is reproduced to an acceptable degree. The predicted CCV is found to be closely related to the difference in the turbu- lence field near the spark plug around the time of spark discharging, which is consistent with the previous LES studies. The current results also suggest the importance of capturing the variations of the laminar-to-turbulent flame transition in predicting CCV.

• Research Organization: The Ohio State University
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
• DOE Contract Number: EE0007334
• OSTI ID: 1513503
• Country of Publication: United States
• Language: English