| Abstract |
Microalgae are considered one of the most promising feedstocks for biofuels. However, the influence of turbulence on algae growth needs to be clarified to effectively scale-up photobioreactors and to operate them reliably for long periods. Algae require sunlight, water, carbon dioxide, nitrogen and phosphorus for their oxygenic photosynthesis. Turbulence in photo-bioreactors plays a key role for algae growth by enhancing mixing, allowing a homogeneous distribution of nutrients and an appropriate exposure of algae to sunlight (bioreactors exterior). However too intense turbulence will damage algae and will reduce productivity. We will investigate, through massively parallel simulations with pseudospectral and Lattice Boltzmann codes, the effects of turbulence and algae concentration, from dilute to dense suspensions (normal operating regime). The knowledge of the multi-scale statistics of turbulent fluctuations, down to the individual alga, is key to develop models necessary to up-scale photo-bioreactor, select algae strain, optimize algae productivity and reduce bioreactors energy consumption. |
