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本文使用商业计算流体力学软件FLUENT 14.0内欧拉-欧拉双流体模型对带有搅拌桨的鼓泡式光生物反应器内气液两相流动进行了模拟,研究了总输入功率(鼓泡功率和搅拌功率之和)一定时,不同的搅拌桨转速对流场特征、搅拌耗功所占总功率之比、藻液光梯度方向速度和湍流涡尺度等的影响.结果表明,与纯鼓泡式反应器相比,使用搅拌桨能够在很低的搅拌功耗情况下显著增强藻液在光梯度方向上的流动.但转速过大时产生的湍流涡会对微藻造成剪切力伤害,在实际培养中可根据藻种的形状大小选择最佳转速值.“,”In the present paper,the Euler-Euler model in the commercial computational fluid dynamics(CFD) code FLUENT 14.0 was used to simulate the flow field of gas-liquid in the bubble-culumn photobioreactor with an impeller.The impact of the impeller speed on the characteristics of flow field,percentage of impeller power consumption,velocity of liquid along light gradient and micro-eddy length scale was studied as the total input power (the sum of power consumption of gas sparger and agitation) stayed the same.The result shows that,compared to bubble-column photobioreactor,the impeller can significantly enhance the liquid flow along light gradient with low power consumption.However,the micro-eddies brought by turbulence at high impeller speed can also do damage to microalgae.So the optimal impeller speed should be chosen according to the shape and size of the nicroalgae in the process of cultivation.