A Pressure-Sensitive Approach for the Transient Analysis of Uniformly Distributed Demands

John Twyman

Resumen


In the modelling of water distribution systems is common to assume that water demands are located at the junctions, with a constant and previously known value. This assumption allows simplify the mathematical analysis of the problem, even when in some cases is more suitable to model the water demand assuming that it has a magnitude which is pressure-sensitive. In this article an original pressure-sensitive approach is proposed to calculate the state variables (flow and pressure) in a pipe with uniformly distributed demands. The general conclusion is that the approach based on the pressure-sensitive demand, compared with the usual method of the pressure-insensitive demand, shows significant attenuation in pressure which may condition the design and/or operating procedure of some devices such as valves or air chambers. 


Palabras clave


Method of Characteristics; Newton-Raphson; pressure-insensitive demand; pressure-sensitive demand; transient flow

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