3.4 Implications
Our results show that the computational model can predict the deformation of biofilms under fluid flow. Biofilms often are spatially heterogeneous in morphology and mechanical properties, which makes the prediction of their mechanical behavior more complex. Moreover, the biofilm boundary is also complex and influences the response. In our research, we studied a synthetic biofilm and a real (homogenized) biofilm. Future studies should address real biofilms with greater mechanical heterogeneity, and more complex geometries. Such studies could help clarify when the average mechanical properties are suitable for predicting deformation, and when variable properties are needed. Moreover, effects of complex boundaries should be addressed.
The PF model’s ability to simulate large deformations, and its versatility with respect to the type of constitutive equations and mechanical properties, makes it useful for a wide range of problems. It also could be expanded to include biofilm growth, allowing the assessment of deformation under timescales where growth could be significant. It also could include multiple phases within the biofilm matrix, such as voids or solid precipitates, or spatially variable mechanical properties. The model would be ideal to study the effect of biofilm disruptors, which diffuse into the biofilm and weaken the EPS matrix, on biofilm removal.
A weakness of the model is that the numerical instability of Oldroyd-B constitutive equation could limit its use for higher velocity ranges and a larger relaxation time scales. However, some of these computational problems could be reduced using sharp interface and extra stabilization methods. Finally, detailed 3D simulations under complex flow regimes would require large computational recourses.