Comprehensive Computational Model for Combining Fluid Hydrodynamics, Light Transport and Algal Growth Kinetics in a Taylor Vortex Reactor

A comprehensive modeling method for simulating algae growth in a Taylor vortex reactor is introduced. The method bridges fluid hydrodynamics, detailed light transport, and algae growth kinetics. Previous semi-batch experimental work shows that algal growth in a Taylor vortex reactor is not limited by mixing and mass transfer, and nutrient limitation only exists at high biomass concentration. In the present model we assume that biomass growth is only light limited. We first formulate the overall reactor simulation model by coupling a computational fluid dynamics (CFD) model to account for transport of microorganisms in the reactor, a multidimensional radiation model to accurately compute light distribution in the reactor, and a photosynthetic units (PSU)-based model for biomass growth. In particular, the method for coupling the model components and fitting of model parameters is discussed. Subsequently, simulation predictions are validated against corresponding experiments, and we demonstrate good agreement between the simulations and the experiments. This comprehensive model has the capability to simulate mixing induced light/dark cycles and can provide guidance for the rational design and optimization of production scale bioreactors for cultivation of microalgae.