The effects of piloting on turbulent flame structure

Pilot flames are commonly used to study turbulent flames as they present a means of preventing blow off at higher velocities. There are open questions regarding how pilot flames affect the main flame. This is true for both anchoring pilots, which are small pilot flames located at the base of the flame, and back-support pilots, which produce adiabatic or superadiabatic boundaries around the flame. The question of how the presence and size of pilot flames affect the properties of the main flames is important to understanding the behavior of the main flame. The purpose of this study is to explore how the presence of pilot flames affects the flame surface density, global consumption speed, and flame curvature statistics of a turbulent, premixed flame over a range of velocities. Natural gas was used as a fuel and the equivalence ratio was held constant at 1. Three different pilot flame configurations were used to explore the interaction between flame and pilot, including variations in the presence of both the anchoring pilots and the back-support pilots. The results of this study will affect our interpretation of flame sheet dynamics in a range of piloted flames.