Adaptive mixed FEM combined with the method of characteristics for stationary convection–diffusion–reaction problems

[Abstract]: We consider a stationary convection–diffusion–reaction model problem in a two- or three-dimensional bounded domain. We approximate this model by a non-stationary problem and propose a numerical method that combines the method of characteristics with an augmented mixed finite element procedure. We show that this scheme has a unique solution. We also derive a residual-based a posteriori error indicator and prove it is reliable and locally efficient. Finally, we provide some numerical experiments that illustrate the performance of the adaptive algorithm.