Effects of standing sound wave on droplet combustion
Tóm tắt
Combustion of an isolated fuel droplet in acoustic fields is investigated by microgravity experiments. The influence of standing sound wave is examined by varying amplitude of velocity fluctuation, frequency of sound and location of droplet. Variation of flame shape and burning rate is determined. As a result, spreading flame to one direction as well as normal gravity is observed as amplitude of velocity fluctuation increases. On the other hand, hemispheric and conical flames are observed when the amplitude of velocity fluctuation is small. Direction of flame spread is changed depending on relative location between velocity anti-node and the droplet. The cause is considered as acoustic radiation force in standing sound wave. Burning rate is significantly enhanced by velocity fluctuation and the amount of the enhancement is changed by sound frequency or relative location.
Tài liệu tham khảo
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