title: Multicomponent model of deformation and detachment of a biofilm under fluid flow.
abstract: A novel biofilm model is described which systemically couples bacteria, extracellular polymeric substances (EPS) and solvent phases in biofilm. This enables the study of contributions of rheology of individual phases to deformation of biofilm in response to fluid flow as well as interactions between different phases. The model, which is based on first and second laws of thermodynamics, is derived using an energetic variational approach and phase-field method. Phase-field coupling is used to model structural changes of a biofilm. A newly developed unconditionally energy-stable numerical splitting scheme is implemented for computing the numerical solution of the model efficiently. Model simulations predict biofilm cohesive failure for the flow velocity between [Formula: see text] and [Formula: see text] m s(-1) which is consistent with experiments. Simulations predict biofilm deformation resulting in the formation of streamers for EPS exhibiting a viscous-dominated mechanical response and the viscosity of EPS being less than [Formula: see text]. Higher EPS viscosity provides biofilm with greater resistance to deformation and to removal by the flow. Moreover, simulations show that higher EPS elasticity yields the formation of streamers with complex geometries that are more prone to detachment. These model predictions are shown to be in qualitative agreement with experimental observations.
authors: Mathematical Institute, Faculty of Mathematics and Physics, Charles University, 186 75 Prague 8, Czech Republic Department of Applied and Computational Mathematics and Statistics University of Notre Dame, Notre Dame, IN 46556, USA.
authors: Giordano
authors: G
authors: Tierra
authors: Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Santiago, Chile.
authors: Juan P
authors: http://orcid.org/0000-0002-7614-3572
authors: JP
authors: Pavissich
authors: Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
authors: Robert
authors: http://orcid.org/0000-0003-2203-5004
authors: R
authors: Nerenberg
authors: Department of Applied and Computational Mathematics and Statistics University of Notre Dame, Notre Dame, IN 46556, USA.
authors: Zhiliang
authors: Z
authors: Xu
authors: Department of Applied and Computational Mathematics and Statistics University of Notre Dame, Notre Dame, IN 46556, USA malber@nd.edu.
authors: Mark S
authors: MS
authors: Alber
mesh_terms: D001419:Bacteria / Q000166:cytology*; D001422:Bacterial Adhesion / Q000502:physiology*; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development*; D048429:Cell Size; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology; D044085:Microfluidics / Q000379:methods*; D008954:Models, Biological; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D033081:Shear Strength / Q000502:physiology; D013314:Stress, Mechanical
chemical_list: D011135:Polysaccharides, Bacterial
keywords: biofilm; continuum mechanics; detachment; energetic variation; phase-field model; viscoelasticity