## Fluids

#### How to make a pipe flow in a horizontal way

• Raj1996
Subscriber

Hello. So ive made a 90 degree pipe. How do i make the flow to be in a horizontal way?

Ansys Employee

Regards,

Keyur

• Raj1996
Subscriber

This is the pipe that i will be using. The longer section being the inlet and the shorter end being the outlet. I am simulating a two phase emulsion flow using VOF method. How do i make the flow to be in a horizontal way? Like it is flowing parallel to the ground.

Thank you.

Ansys Employee

Please use gravity in X direction.

You can also check following.

Regards,

Keyur

• Rob
Ansys Employee

You also need alot more mesh to use the VOF model in this way: see my comment in your other thread   https://forum.ansys.com/forums/topic/emulsion-simulation-in-a-pipe/

• Raj1996
Subscriber

Hello friends. Thank you so much for knowledge and instructions shared. However there are still some sections that i am in doubt. My goal is to observe the emulsion flow throughout the pipe. Below are certain things that i am not sure of.

1) The fluid at the inlet that i need to use is mixture of oil at various water cuts. Such as oil with 10%, 20%, 30% water. In this case, is my inlet phase to be set as mixture or oil at the boundary conditions tab? What i have previously tried to do was that i set the inlet phase to be mixture and to set the volume fraction for the water as the amount i require such as 0.1, 0.2, 0.3. The outlet phase was set at mixture and type set to pressure-based. Is this the right way?

2) Do i need to  create regions if my inlet flow is going to be a mixture of oil and gas?

3) The surface tension coefficient value that i am applying is currently 0.075 n/m based on youtube tutorials. Is there a specific value to be used for oil and water surface tension?

My solution method is currently Scheme: Coupling, Gradient: Least squared, Pressure: Presto, Volume fraction: Compressive and the others set at second order.

Your help is very much appreciated and i would also like to thank you guys once again.

• Rob
Ansys Employee

As ANSYS staff we can't answer too specifically on a public forum: the wider community can.

Re surface tension, read up on the subject: different materials have different surface tension values. You also need to work out what sort of oil you're using as "oil" covers anything from olive oil to Saudi Heavy bitumen!

Have you read up on the VOF and Eulerian multiphase models in the documentation? You'll need R19 for this, but the sections on Multiphase will answer most of your questions re the boundary conditions.