Well fracture modelling

Method for calculating flow conditions in fractures in the vicinity of a well bore, the well fracture being defined by a two-dimensional network of nodes and links describing flow paths intersecting a geological formation, the geological formation defined in terms of three-dimensional grid cells and allowing a fluid flow between said formation grid cells and the fracture, and from the fracture to the well, the method includes:

• a) iterative solution of the well flows contingent on boundary conditions from the formation, the well bottom hole pressure being varied from one iteration to the next until all of a plurality of well constraints are satisfied to a predetermined tolerance or a chosen iteration number;
• b) at each iteration, this involves a non-iterative solution of any fracture flows contingent on the well pressures and the boundary conditions from the formation grid cells, the pressure solution of the linear system of equations for any voidage flows in the fracture defines the individual drawdowns for each of a plurality of cell-fracture connections determining the component rates between the formation and the fracture.