Study Of Experiments And CFD Simulation Of Open Circular Pond And Open Raceway Pond Photo-bioreactor For Energy Microalgae

Open circular pond photo-bioreactor for energy microalgae was systematic studied in this paper. The flow field test, CFD simulation, model validation, optimize of paddle types and operation modes and scale-up rule of circular pond were carried out, while continuing to study on raceway pond.First of all, Characteristics of flow field of hydrofoil impeller and four-pitched-blade turbine(PBT) in circular pond were investigated employing PIV. The results showed that the flow field, contours of velocity and velocity of hydrofoil impeller and PBT were accurately obtained by CFD, the CFD model was consistent with the PIV-measured on the whole. The model of CFD was correctly and can be used for the scale-up of the circular pond.Then one small circular pond with and without baffles, pros and cons of two paddle-types and operation modes between hydrofoil impeller and PBT were studied by CFD simulation, the results showed that hydrofoil impeller was better than PBT and down-flow operation was better than up-flow operation; Culture experiments were carried out in small and medium-sized circular ponds, the culture experiments verified the CFD simulation.On the basis of previous study, a circular pond scale-up method was proposed which the average velocity magnitude along the light direction Vz as a reference, two scale-up equations were respectivily obtained on operation of down-flow and up-flow, VZ=0.05899Pv03386T-1.2057andVZ=0.0516Pv0.3221T-1.125.On the basis of previous study on raceway pond, I continued to do the research between adding single and double paddle wheel, between adding guiding baffles and no guiding baffles. The results showed that adding double paddle wheel was better than adding single paddle wheel, add the guiding baffles was superior to not add guiding baffles.