V. Dehenau et Gd. Raithby, A TRANSIENT 2-FLUID MODEL FOR THE SIMULATION OF SLUG FLOW IN PIPELINES .1. THEORY, International journal of multiphase flow, 21(3), 1995, pp. 335-349
A one-dimensional transient two-fluid model is developed to predict tr
ansient slug flow in pipelines. To account for the interphase interact
ions, new constitutive relations for the drag coefficient and the virt
ual mass force for the slug flow regime are derived by applying the co
nservation equations to a geometrically simplified slug unit. New coef
ficients in the pressure gradient term in the two-fluid momentum conse
rvation equations are also obtained to account for the non-uniform dis
tribution of the phases and of the pressure drop along a slug unit. Th
e new relations yield a more accurate treatment of the hydrodynamics o
f slug flow than traditional two-fluid models. Constitutive relations
for other Bow regimes can also be incorporated into the model, allowin
g the analysis of general transient two-phase flows in pipelines.