[YukiW]

Hi all,

I am doing the simulation of the three-phase slug simulation for my research project. I have some problems about it, the main one is that I can't develop slug with the conditions used in the experiment.

Following are my simulation conditions:

Mesh: 6000mm*78mm (I tried 2D first)
Three inlets for air/oil/water on the left.

2D ,planar? Unsteady, 1st-Order Implicit Standard k-epsilon turbulence model Standard Wall Functions

surface tension: oil-water 0.03

boundary conditions:
air/oil/water inlets: velocity inlet, Vair=4m/s Voil=Vwater=0.5m/s
pressure outlet. 0Pa
wall:no-slip

initialization : Vair=4m/s Voil=Vwater=0.5m/s, air takes up the up half of the pipe, liquid takes the another half. Water cut= 0.4 liquid hold up. Stratified flow at the beginning.

The case runs about 10s with no other problems, but I can't get any slug in the pipe, only very small waves near the inlet, so I would say the flow remains stratified no matter how I change the velocities.


My opinion is maybe I should change planar into other 2D space but I dont know which one is suitable.

Could you please help me? Many thanks.

Yuki