Basic biofilm models are based on three principles. First, they must incorporate some kind of transport mechanisms (diffusion, advection) for bringing nutrients to the active material in the biofilm. Second, biofilm models usually require some consumption and growth mechanisms. Third, biofilm models require some mechanisms for biofilm necrosis and loss.
In this work we propose a new biofilm model which takes into account the three aspects mentioned before, and study the numerical aspects for its simulation. For modeling the transport of nutrients into the biofilm, we have used a steady-state diffusion equation. For modeling the consumption and growth mechanism, we have modeled the biofilm as a viscous fluid, which is flowing according to the Hele-Shaw model. The key feature of this approach is the fact that the interface between the biofilm and the liquid medium is an unknown of the problem. Thus, in order to reconstruct the motion of the interface, we have used the level set method. Moreover, in order to solve the pressure equation we have used the so-called immersed interface method, which was specially developed for problems with discontinuities. In this talk we will show the numerical methods and some numerical experiences which illustrate the simulation of our model.