Derivation of equivalent pipe network analogues for three-dimensional discrete fracture networks by the boundary element method

Discrete fracture network (DFN) models generally require solution of flow and transport equations in three-dimensional networks of either disc, polygonal, or pipe elements. Pipe network elements have significant advantages in computation for both flow and transport. However, there is a need to develop an efficient procedure for derivation of the properties of these pipes to ensure that they are hydraulically equivalent to the DFN network of polygonal elements. In this study a boundary element procedure for derivation of pipe properties is developed and demonstrated. The results show that the hydraulic behavior of pipe networks can be equivalent to that of polygonal-element DFN models.