论文信息 - Study of fluctuation in fire with photoelectric sensor: assessment of the procedure

Study of fluctuation in fire with photoelectric sensor: assessment of the procedure

Fire fluctuation is caused by internal physic-chemical changing mechanism and variations of external environment. The study of fire fluctuation will help to predict developing tendency of fire and to understand the structure and stability of flame. Several parameters can represent the fluctuation of fire, such as velocity, temperature and optical scattering. The transparency of fire changes with flow state in fire plume. Thus, light attenuation-time history of fire is corresponding to fire fluctuation. A technology utilizing laser-based photoelectric pairs as sensors to measure fire fluctuation in intermittent and smoke zone of a pool fire is described here. In this technique, joint time frequency analysis (JTFA) algorithm is used to determine the frequency change of fire fluctuation during combustion procedure. Ethyl-alcohol and gasoline fire were studied with this technique and the results are presented here. Some limitations of this method are also briefly discussed.

Qiang Xu | Guangxuan Liao

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