A priori and a posteriori error estimation for finite element approximation of advection-diffusion-reaction equation with spatially variable coefficients

This paper presents a study of finite element error estimation of advection-diffusion-reaction equation with spatially variable coefficients. We have derived a priori and a posteriori errors in both energy and L2 norm. We have used residual-based a posteriori error estimator. Numerical results are also presented to verify our theoretical approach.