Hybrid RANS-LES Simulation of In-Cylinder Air Flow for Different Engine Speeds at Fixed Intake Flow Pressure

The in-cylinder flow and mixture formations are
significant in view of today’s increasing concern on environmental
issues and stringent emission regulations. In this paper, the numerical
simulations of a SI engine at different engine speeds (2000-5000
rpm) at fixed intake flow pressure of 1 bar are studied using the AVL
FIRE software. The simulation results show that when the engine
speed at fixed intake flow pressure is increased, the volumetric
efficiency of the engine decreases. This is due to a richer fuel
conditions near the engine cylinder wall when engine speed is
increased. Significant effects of impingement are also noted on the
upper and side walls of the engine cylinder. These variations in
mixture formation before ignition could affect the thermodynamics
efficiency and specific fuel consumption that would lead to a reduced
engine performance.

• L. V. Fui
• A. Ulugbek
• S. S. Dol

• AVL FIRE
• fuel mass
• IC engine
• LES
• RANS
• turbulent intensity.

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