화염의 유동장과 온도에 따른 동축류 확산화염의 불안정 특성 = Flow and Temperature Characteristics When Co-Flow Diffusion Flames Become Unstable

다국어 초록 (Multilingual Abstract)

Flow and temperature characteristics were investigated when co-flow diffusion flames become unstable. Soot concentration, temperature and velocity profiles of diffusion flames were measured using a laser light extinction method and modulated LII signals near the smoke-points or unstable conditions. For methane and ethane diffusion flames, soot concentration is low and flame temperature remains high, and therefore, the flame becomes unstable when the fuel flow rate increases. For ethylene and propylene diffusion flames, however, soot concentration is high and flame temperature becomes low, and the flame starts to emit soot before it becomes unstable with the increase of fuel flow rate. For propane and n-butane diffusion flames, the flame becomes unstable and emits soot at the same time when the fuel flow rate is increased. When soot concentration becomes high, the increased radiation heat loss lowers the flame temperature, and therefore, the flame tends to emit soot before it reaches to the unstable condition. On the other hand, when the soot concentration in a flame is low, the flame temperature remains high since the radiation heat loss is less. As a result, the flame can be long enough to become unstable or the flow velocity can be accelerated fast enough to develop the instability.

목차 (Table of Contents)

• ABSTRACT
• 1. 서론
• 2. 실험장치 및 방법
• 3. 실험결과 및 고찰
• 4. 결론
• 참고문헌