A222 高圧条件下における予混合気自着火及び火炎伝播の直接数値計算(OS-1:火災安全・燃焼(5))

Abstract

Direct numerical simulations of autoignition have been conducted to clarify effects of length scale in flow and temperature field and initial temperature fluctuations on turbulent combustion mechanisms in homogeneous charge compression ignition engines. Methane-air mixtures at high pressure with spatial inhomogeneity of temperature are investigated by considering a detailed kinetic mechanism. For the case with lower temperature fluctuations, local autoignition starts later at smaller length scale due to larger effects of turbulent and molecular diffusion before the autoignition, while effects of length scale is relatively weak for high temperature fluctuations. Lagrangian fluid particle tracking method is conducted to identify combustion regimes under the different length-scale conditions.