COMPREHENSIVE STUDY OF COMBINING FLOW CONDITIONS AT PIPE JUNCTIONS

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COMPREHENSIVE STUDY OF COMBINING FLOW CONDITIONS AT PIPE JUNCTIONS

A theoretical and experimental investigation into the behavior of pipe junction,either 45 or 90 degree,has been performed. The junction was formed by the meeting of three equal diameter pipes which all had equal invert levels. The characteristics of each type of junction were examined and revised empirical equations describing the now conditions at the junctions were developed. These equations are then incorporated into the computer program, based upon the numerical solution of St. Venant equations using characteristic-diffference method, to route unsteady flows beyond computational boundaries formed by such components. The presented equations may also be used to determine the limiting capacity of a junction if surcharge of the system is to be avoided. Excellent agreement is found to exist between the observed unsteady flow conditions at the junction and those predicted using the derived relationships.