Investigation of Combustion Regimes in Super Lean-burn SI Engines Using the Turbulent Combustion Diagram

Abstract

Combustion regimes of super lean-burn were investigated in order to realize stable combustion for every cycle. Laminar burning velocity, flame thickness, turbulent intensity, and integral length scale were calculated, and the crank angle history of turbulent Karlovitz number was shown on the regime diagram for premixed turbulent combustion suggested by Peters. The result showed that the effect of quenching due to flame stretch is larger during initial combustion duration because turbulent Karlovitz number is larger in super lean-burn conditions, and an interpretation was given regarding the combustion regime of super lean-burn different from general flame propagation.