KWRRI Research Reports


Algorithms for analyzing steady state flow conditions in pipe networks are developed for general applications. The algorithms are based on both loop equations expressed in terms of unknown flowrates and node equations expressed in terms of unknown grades. Five methods, which represent those in significant use today, are presented. An example pipe network is analyzed to illustrate the application of the various algorithms. The various assumptions required for the different methods are presented and the methods are compared within a common framework.

The reliabilities of these commonly employed algorithms for pipe network analysis are investigated by analyzing a large number of pipe networks using each of the algorithms. Numerous convergence and reliability problems are documented. It is shown that two methods based on loop equations have superior convergence characteristics. Methods based on node equations are less reliable and these methods are often unable to adequately handle low resistance lines. A discussion of convergence criteria and solution reliability is presented for the various algorithms. The results presented in this report will allow engineers to accurately carry out pipe network analyses.

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Funding Information

The work upon which this report is based was supported in part by funds provided by the Office of Water Research and Technology, United States Department of the Interior, Washington, D.C., as authorized by the Water Research and Development Act of 1978. Public Law 95-467.

This work was supported by a grant from the Kentucky Water Resources Research Institute under project A-076-KY and a grant from the Office of Water Research and Technology, U.S. Dept. of Interior, under project B-060-KY.