Numerical analysis of the effects of air on light distribution in a bubble column photobioreactor
McHardy C, Luzi G, Lindenberger C, Rodríguez Agudo J, Delgado A, Rauh C (2018)
Publication Status: Published
Publication Type: Journal article, Original article
Publication year: 2018
Journal
Publisher: ELSEVIER SCIENCE BV
Book Volume: 31
Pages Range: 311-325
DOI: 10.1016/j.algal.2018.02.016
Abstract
Light distribution inside photobioreactors (PBR) is a crucial parameter for the determination of growth of phototropic microorganisms and reactor productivity. In order to compute the light propagation inside PBR, scattering due to the presence of microorganisms is often neglected, since it is difficult to measure experimentally and it is not trivial to handle numerically. Moreover, absorption is usually assumed constant, but it is affected by the concentration of microorganisms and the presence of gas bubbles. In the present contribution we study how the flow hydrodynamics and local gas fractions inside a bubble column PBR affect the light distribution. First, we perform numerical simulations of a bubble column flow at different gas superficial velocities. Afterwards, we use instantaneous air volume fractions to calculate the effective scattering and absorption coefficient of the mixture, as well as the effective scattering phase function. Finally, we compute the polychromatic light distribution inside the PBR by means of a Lattice-Boltzmann solver. On the one hand, we find that gas bubbles affect both spatial distribution and magnitude of the light intensity field and their impact increases at higher gas superficial velocity. On the other hand, we also observe that the biomass counteracts these effects already at concentrations less than 1 kg/m(3) so that the role of the gas phase on light fields seems to be of minor importance in PBR.
Authors with CRIS profile
Giovanni Luzi
Lehrstuhl für Strömungsmechanik
Christoph Lindenberger
Department Chemie- und Bioingenieurwesen
José Rodríguez Agudo
Department Chemie- und Bioingenieurwesen
Antonio Delgado
Lehrstuhl für Strömungsmechanik
Cornelia Rauh
Involved external institutions
Germany (DE)How to cite
APA:
McHardy, C., Luzi, G., Lindenberger, C., Rodríguez Agudo, J., Delgado, A., & Rauh, C. (2018). Numerical analysis of the effects of air on light distribution in a bubble column photobioreactor. Algal Research, 31, 311-325. https://dx.doi.org/10.1016/j.algal.2018.02.016
MLA:
McHardy, Christopher, et al. "Numerical analysis of the effects of air on light distribution in a bubble column photobioreactor." Algal Research 31 (2018): 311-325.
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