High EGR Rate, Lean TRF-air Turbulent Combustion with Tumble Flow in a Constant Volume Vessel

To investigate the flame characteristics under a high efficiency spark ignition engine condition, a direct numerical simulation (DNS) of forced ignition of premixed mixtures in a constant volume vessel with a tumble flow has been performed for a lean Toluene Reference Fuel (TRF)-air mixture at a high exhaust gas recirculation (EGR) rate at high pressure. After a certain time, separated reaction region is observed. It is found that flame characteristics just after the ignition region are close to the corresponding laminar flame and flame characteristics of separated reaction region are different from laminar flame.