COMPARISON OF TWO MODELS FOR TRANSIENT FLOW OF LIQUIDS IN PIPELINES

Abstract

The work on the solution of liquid column separation in pipelines started as early as the 1930's of the last century. Early efforts were based on the investigations of the experimental works in search for a robust method to model and simulate the phenomena mathematically. In the late 1960's, a numerical model known as discrete vapor cavity model emerged, which is still in exclusive use up to the present time. The model became the main reference for most of subsequent works, which in turn contributed to the development and improvement of the model. in this paper, a thorough comparison is made between two approaches used to solve problems of column separation phenomenon; the well known Streeter's approach developed in 1969, and Carmona's approach developed in 1988. Both approaches are based on the vapor cavity model. The setup analyzed by Carmona is selected for the purpose of comparison, with different steady state conditions, by applying both approaches to the same pipeline system. The obtained results showed that the solution of the cavity as an adiabatic process suggested by Carmona, give better agreement with experimental data, than the famous Streeter's approach