A comparative experimental study of turbulent non premixed flames stabilized by a bluff-body burner

• PIV and OH-PLIF measurements are discussed for three bluff body turbulent flames.
• Flame generates turbulence in intermittently lifted situations.
• Combustion suppresses part of the Reynolds stresses when fully lifted.

Turbulent non-premixed flames of natural gas and air stabilized in a semi-infinite bluff-body burner are assessed in this work. Different situations are investigated corresponding either to jet or to wake-dominated flow fields. Measurements of the OH radical fluorescence and of the velocity field are obtained by joint Planar Laser Induced Fluorescence (PLIF) and Particle Image Velocimetry (PIV) techniques. First, a study of two chemically inert cases is presented to base the flow field structure. Then, the instantaneous OH fluorescence and velocity fields analysis underscore the local extinctions and the interactions between combustion and turbulence. A comparison between the Reynolds stresses distribution reveals that the flame presence generates turbulence in intermittently lifted situations and suppresses part of the Reynolds stresses when fully lifted.