MIXED SPECIFICATION PROBLEMS IN LARGE-SCALE PIPELINE NETWORKS

The solution of pipe network problems can usually be obtained by ortho gonal mesh and nodal approaches. However, when the size of a network b ecomes very large, these methods may not be efficient. In such a case diakoptics may be used. Essentially this approach tears the given netw ork into two or more smaller subnetworks, thereby reducing the size of the matrices involved and saving computation time. So far most resear ch in the area of diakoptics has been confined to problems where all t he external flows are specified. Although the fictitious branch method has been incorporated into diakoptics to solve mixed flow- and pressu re-specified problems it cannot satisfactorily solve problems with man y pressure specified nodes. In the present work, a method for solving mixed specification problems is developed based on mesh and nodal diak optics, incorporating partitioning. The diakoptics technique for the s olution of mixed specification problems is found to be more efficient than conventional partitioning methods. (C) 1998 Elsevier Science S.A. All rights reserved.