关键词: 波纹隔板, 流动混合, 气含率, 溶氧体积传质系数, 计算流体动力学

Abstract: A novel panel photobioreactor with two wavy baffles for improving flow and mixing is presented. Both experiments and computational fluids dynamics (CFD) simulation were conducted to detect the hydrodynamic characteristics of the panel including flow, averaged gas holdup, volumetric mass transfer coefficients and the ratio of cycle time of liquid between riser and downcomer. It was found that the CFD simulation agreed well with experimental results. The wavy baffles used resulted in a good circulation flow between riser and downcomer. With the increase of aeration rate, liquid flow velocity, averaged gas holdup and volumetric mass transfer coefficients increased near linearly. There was a good linear relationship between averaged volumetric mass transfer coefficient and volumetric power input. Considering related factors, an optimized structure of the panel with wavy baffles was obtained as the ratio of cross-section area of the downcomer and the riser 1.62, clearance from the upper edge of the baffles to the water lever 260 mm, and clearance from the lower edge of the baffles to the bottom of the reactor 20 mm.

Key words: wave-baffled panel, flow and mixing, gas holdup, volumetric mass transfer coefficien, computational fluids dynamics