Coherent Structure Behavior of laminar non-premixed flame under acoustic excitation : 음향 가진된 충류 벼예혼합 화염의 거대와 구조 거동 = School of Automotive Engineering, Provincial College of Damyang

다국어 초록 (Multilingual Abstract)

A visualization study on the effect of forcing amplitude in tone-excited non-premixed jet flames has been done at a resonant frequency of fuel tube. Visualization techniques are employed using optical schemes, which are a light scattering photography. Flame stability curve is attained according to Reynolds number and forcing amplitude at a resonant frequency of fuel tube. Flame behavior is globally grouped into two from attached flame to blown-out flame according to forcing amplitude; one sticks the tradition flame behavior which has been observed in general jet diffusion flames and the other shows a variety of flame modes such as the flame of a feeble forcing amplitude where traditionally well-organized vortex motion evolves, a fat flame, an elongated flame, and an in-burning flame. Particular attention is focused on an elongation flame, which is asso챠ated with a tumabout phenomenon of vortex motion, and on a reversal of the direction of vortex roll-up. It is found that the flame length with forcing amplitude is the direct outcome of the evolution process of the formed inner flow structure. Especially the negative part of the acoustic cycle under the influence of a strong of negative pressure gradient causes the shapes of the fuel stem and fuel branch part and even the direction of vortex roll-up to dramatically change.

목차 (Table of Contents)

• INTRODUCTION 1
• Experimental Apparatus and Method 2
• RESULTS AND DISCUSSION 3
• CONCLUDING REMARKS 9
• ACKNOWLEDGEMENT 9
• REFERENCES 9