1999 Volume 65 Issue 633 Pages 1813-1821
The mixing characteristics and flame holding mechanism inside a model ram combustor was experimentally investigated by using a Fiber Laser Doppler Velocimeter (FLDV) under non-reacting and reacting conditions down-stream of the bluff body type flame holder. The FLDV was optimized regarding the high flow speed and combustion. The evaluation of the FLDV measurement system and a new data analysis method, called Slot-Correlation, were applied. The results of the reacting experiment presented a striking contrast to that of the non-reacting flow. The jet penetration and the reverse flow regions were found to have three-dimensional structures. The Slot-Correlation method was applied to evaluate the turbulent structure around the strong shear layer behind the bluff body. Distribution of integral scales inside the shear layer and oscillations at the end of the recirculation zone were captured.