STUDY OF PRESSURE TRANSIENTS IN PIPE LINES

Abstract

The applicability of the Center Implicit Method (CIM) to pressure transients in pipelines is investigated in terms of the stability, accuracy and the computer time requirement. A comparison is made between CIM and the Method of Characteristics (MOC) and the results indicate good agreement when stability criteria are satisfied. The pressure transient equations for flows in a pipe line are derived considering a two dimensional velocity profile across the pipe section. The equations are solved by CIM. The numerical results show good agreement with those data that were obtained experimentally. The experiments were carried out on a 2m long vertical pipe with two sensitive pressure transducers fitted at both ends. The pressure transients in the test pipe were effected by an electrically actuated solenoid valve, and the experimental data were collected by a high speed data acquisition system. A further comparison is also made between the results of the two dimensional model solved by CIM and experimental results reported by other investigators and found to have good agreement. The 2D theoretical analysis is also extended to two phase bubbly flow with air and water, to investigate the effect of wave speed on the two dimensional model. Experimental and theoretical results of the two phase flow investigation are also presented.