TRANSIENT PHENOMENA IN TWO-PHASE HORIZONTAL FLOWLINES FOR THE HOMOGENEOUS, STRATIFIED AND ANNULAR FLOW PATTERNS

The nature of horizontal two-phase transient flow in pipes has been studied from a flow pattern perspective. The assumption of isothermal flow conditions reduces the analysis to the numerical solution of a set of equations representing the conservation of mass and linear momentum for the two simultaneously flowing phases, for each of the three flow patterns under consideration. An analytical flow pattern prediction model derived from physical principles has been used as the criterion for switching from one equation set to another. Interfacial mass transfer effects have been included. Data confirming the validity of the model were generated from an existing 1378 ft long, 3 inch diameter horizontal pipeline. The inclusion of an intermittent flow model to the present formulation will result in a comprehensive transient flow prediction model for horizontal isothermal flow, valid for the entire range of flow patterns encountered.