Simultaneous 10 kHz repetition-rate tomographic particle image velocimetry, hydroxyl planar laser-induced fluorescence (OH PLIF), and formaldehyde (CH (Formula presented.) O) PLIF were used to study the structure and dynamics of turbulent premixed flames. The flames investigated span from the classically defined corrugated flamelet regime to conditions at which broadened and/or broken flamelets are expected. Methods are presented for determining 3D flame topologies from the Mie scattering tomography and for tracking features through space and time using theoretical Lagrangian particles. Substantial broadening of the CH (Formula presented.) O region is observed with increasing turbulence intensity. However, OH production remains rapid, and the region of OH and CH (Formula presented.) O overlap remains thin. Local flame speeds exceeding three times the laminar flame speed are observed in regions of flame–flame interaction. Furthermore, a method of tracking fluid residence time within the CH (Formula presented.) O layer is presented and shows that residence time decreases at higher turbulence intensity despite the broader distribution of the CH (Formula presented.) O, indicating an increase in local reaction rate.
ASJC Scopus subject areas
- Computational Mechanics
- Mechanics of Materials
- Physics and Astronomy(all)
- Fluid Flow and Transfer Processes