Leak-Induced Pressure Decay During Transients in Viscoelastic Pipes. Preliminary Results☆

In this paper, the dynamics of pressure peaks in a single viscoelastic pipe with a leak (leaky pipe) is examined by means of laboratory and numerical experiments. Experimental tests are the necessary premise to a reliable calibration of a 1-D numerical model which allows to investigate in detail a wide range of both geometrical and flow conditions by taking into account not only the leak but also energy dissipation due to viscoelasticity and unsteady friction. In the analysis, the decay of the maximum values of the pressure is assumed as a representative characteristic of the dynamics of the examined transients in the long term. The numerical campaign has pointed out the characteristic quantities affecting the investigated phenomenon as well as the structure of the pressure decay law.

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