Numerical simulation of fluid flow in a hydrocarbon reservoir has to accoun
t for the presence of wells. The pressure of a grid cell containing a well
is different from the average pressure in that cell and different from the
bottom-hole pressure for the well [17]. This paper presents a study of grid
pressures obtained from the simulation of single phase flow through an iso
tropic porous medium using different numerical methods. Well equations are
proposed for Darcy flow with Galerkin finite elements and mixed finite elem
ents. Furthermore, high velocity (non-Darcy) flow well equations are develo
ped for cell-centered finite difference, Galerkin finite element and mixed
finite element techniques.