Photobioreactor with ideal light–dark cycle designed and built from mathematical modeling and CFD simulation

Abstract Relevant literatures and experiments show that there is a significant influence of light–dark cycles on microalgae yield. In this work, a flat plate airlift photobioreactor with two panels (2-panel PBR) was therefore investigated to obtain prescribed light regime of light–dark cycle and realize highly-effective microalgae cultivation. The governing equations coupled by laminar bubbly flow with microalgae mass transfer equation and boundary conditions were firstly developed to theoretically study the optimum geometric configuration and operating parameters of the 2-panel PBR which were supposed to provide expected light–dark cycle by computational fluid dynamics (CFD) simulation. The 2-panel PBR prototype was then built from mathematical model and digital simulation. Finally, the prototype experiments on microalgae cultivation suggested that the mathematical model was sufficiently valid, and the microalgae Chlorella vulgaris was high-effectively cultivated under the prescribed light regime of light–dark cycle in this 2-panel PBR which could be extensively used in ecological engineering fields and microalgae-based industries.