Abstract A bionic fractal tree-like photobioreactor (PBR) with multiscale bubbles was studied to help intensify gas–liquid mass transfer and the microalgal photosynthesis. A numerical simulation and several experiments were conducted to study the hydrodynamic characteristics of the microbubbles (MBs) and large bubbles (LBs) in the tree-like PBR. The characteristics studied included the bubble size distribution, flow pattern, gas holdup, gas–liquid slip ratio, and turbulence. The good flow characteristic of the MBs tended to generate a homogeneous dispersed flow pattern, which intensified the synergistic effect of flow and light fields based on the long residence time, large gas–liquid contact area, and even multiphase mixing in the large-area illuminated fractal reactor. As a result, the photosynthetic capacity and microalgal activity were enhanced by combining the tree-like PBR with MBs, providing a novel valuable technical solution for improving the multiphase photoreaction.

中文翻译：

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微气泡流和光场对仿生树状光生物反应器的协同作用

摘要 研究了一种具有多尺度气泡的仿生分形树状光生物反应器（PBR），以帮助加强气液传质和微藻光合作用。为了研究树状 PBR 中微气泡 (MBs) 和大气泡 (LBs) 的流体动力学特性，进行了数值模拟和多次实验。研究的特性包括气泡尺寸分布、流动模式、气体滞留率、气液滑移比和湍流。MBs良好的流动特性倾向于产生均匀分散的流动模式，这加强了基于长停留时间、大气液接触面积以及大面积照射下的多相混合的流场和光场的协同效应。分形反应堆。因此，