ABSTRACT

For problems of convection-diffusion type, Eulerian-Lagrangian localized adjoint methods (ELLAM) provide a methodology that maintains the accuracy and efficiency of Eulerian-Lagrangian methods, while also conserving mass and systematically treating any type of boundary condition. In groundwater hydrology, this framework is useful for solute transport, as well as vadose-zone transport, multiphase transport, and reactive flows. The original paper by Celia, Russell, Herrera, and Ewing appeared in 1990, and a review of research on ELLAM was recently published in the 25th anniversary special issue of Advances in Water Resources. This informal background talk will go over the basic concepts of ELLAM.