Flame patterns of acoustic wave and flame interaction in a cylindrical tube

In this short paper, flame and acoustic wave interactions under laboratory conditions have been reported. The test rig consists of a cylindrical Perspex tube and a fuel tube (burner) positioned along the central axis of the tube. The acoustic characteristics of the rig are measured. The flame instability with and without acoustic excitation has been investigated. A high shutter speed colour camera has been applied to capture many interesting unstable flame patterns. It has been found that strong flame instability only occurs at particular frequencies. The position of the burner inside the cylindrical tube also has an effect on flame instability.