【摘要】 小球藻光合作用强,生长速率快,被看作21世纪保健品和生物柴油的潜在来源。大规模成功培养小球藻是将这一潜力变为现实的关键,因而合理设计小球藻生长空间—光生物反应器显得尤为重要。本文研究了两种螺旋管式光生物反应器(Ⅰ型和Ⅱ型),模拟得到了螺旋管反应器内小球藻流体的流动形态,并确定了反应器内小球藻细胞的运动轨迹;根据计算得到的横截面旋流数大小确定了不同反应器的纵向混合性能。结果表明在螺旋管光生物反应器的横截面上能形成很明显的旋涡;对于Ⅰ型和Ⅱ型光生物反应器,对应表征混合性能优越的旋流数分别为0.05到0.15之间和0.25到0.35之间,远高于直圆管反应器(其值接近于0)。更多还原

【Abstract】 With the characteristics of high efficiency of photosynthesis,fast reproduction,Chlorella is regarded as the potential source of health care products and biodiesel in the 21st century.Massive and successful cultivation of Chlorella is the key to turn this potential to reality,therefore,it is of vital importance to properly design the growth space—photobioreactor(PBR) of Chlorella.In this paper,two kinds of PBRs(typeⅠand typeⅡ) are designed.The flow characteristics of Chlorella fluid within the PBRs are obtained through CFD modelling.Then the cell trajectories of Chlorella cells are identified.The mixing performances of different PBRs are determined by numerically calculating their cross-sectional swirl numbers.Results show that strong swirl motions are formed in the cross-sections of the spiral photobioreactor.With high swirl number ranging from 0.05 to 0.15 and 0.25 to 0.35 for typeⅠand typeⅡPBRs,respectively,the mixing performances of the spiral photobioreactors are much better than that of tubular PBR(the values of which are close to 0).更多还原