Solid-liquid flow field in eccentrically stirred tank was investigated by PIV( Particle Image Velocimetry) and solid-state laser generator. An unbaffled, flat bottom, cylindrical glass vessel of diameter 340mm equaling to the liquid height was used. The results show that, the vortices inclined with the vertical plane in eccentric stirred tank, which the turbulent kinetic energy is significant so that they break the flow field coherence, compared with concentric stirred tank. Axial flow is evident and formed a large scale single loop flow field with high eccentricity. Particle concentration has more well-distributed in eccentric stirred tank. The height suspended particles with eccentricity increases, although it lifts the critical suspension speed and power consumption. The effect is best when the eccentricity is equal to 0.4.%在直径为340mm的平底圆筒搅拌槽内,利用PIV和固体激光发生器对固相体积浓度为20％的固液两相体系进行了试验.结果发现,与中心搅拌相比,偏心搅拌时涡轴与搅拌轴倾斜,槽内流体的动力学扰动增大,破坏了中心搅拌时流体流动的一致性.偏心率越大,槽内流体的轴向流动愈明显,并形成一个范围较大的单循环流动结构.偏心搅拌时,颗粒的浓度分布较中心搅拌时均匀得多,颗粒的悬浮高度随偏心率的增大而增大,但临界悬浮转速和功率消耗也随之增大,试验得出最佳偏心率为E=0.4.
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