Opposed jet flames have been used for many years to understand the relationships between flame stretch and quenching under a variety of conditions and for numerous fuels. These measurements have been critical in gaining an understanding of vortex-flame interactions associated with turbulent flames. In this paper, an opposed jet flame is used in a non-traditional way to investigate vortex-flame interactions during the turbulent transition process. The flame interaction with the multiple mushroom vortices generated from the collision of fuel and air jet vortices are studied using a time-dependent computational-fluid-dynamics-with-chemistry (CFDC) code known as UNICORN (UNsteady Iignition and COmbustion with ReactioNs). The combustion process is modeled using a detailed-chemical-kinetics mechanism that incorporates 13 species and 74 reactions. Various visualization techniques are applied to investigate the flame/flow-structure interactions. Sequential images of the vortex/flame interactions over a period of time are studied. It is found that the entrainment of fuel-air mixtures, hot gases and portions of the flame into the wake regions of mushroom vortices enhanced combustion and broadened the reaction (or flame) zone.
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