Abstract

To simulate the complexity of biofilm growth on geometrically complex support structures, 3D pore-scale models are necessary. The lattice Boltzmann (LB) method was used to solve the required coupled hydrodynamics and mass transfer equations because of its proven high performance in simulating these processes in arbitrary complex geometries. The fluid velocity, pressure and solute concentrations fields calculated with LB were coupled with an individual based biofilm growth model (IbM). In order to simulate shear induced biomass detachment, a fast marching level set (FMLS) method has been implemented that models the propagation of the biofilm/liquid interface with a speed proportional to this surrounding shear field. This talk will discuss how and why the presented approach is most applicable to biofilm growth in porous media. The influence of hydrodynamics and nutrient mass transfer on biofilm growth and development in model complex porous media was considered and discussed by comparing the simulation results for constant pressure drop (CPD) and constant volumetric flow rate (CVF) operation modes for the provision of nutrients to the system. It is demonstrated that the resulting biofilm growth and permeability reduction is a complex competition between nutrient supply and detachment.