Effect of turbulent structure on filament-type biofilm reaction

Effect of turbulent diffusion on substrate uptake rate by biofilms was studied. A new turbulent diffusion biofilm model was developed considering profiles of turbulent diffusivity in and over biofilms. A numerical simulation was conducted using a proposed model to show that substrate flux changes with turbulent diffusivity obeying a power law with the coefficient value between 0 and 1. Biofilm was grown in open channels and the effect of short-term changes in turbulence of the overlying flow on substrate flux into the biofilm was measured. Profiles of velocity and turbulent intensity in the overlying flow were measured using a Laser Doppler Velocimeter. It was concluded that the substrate uptake rate by biofilms was dependent on the turbulence near biofilms, the mechanism of which can be explained by the proposed turbulent diffusion model.