Hi, I am using the VOF model to simulate two phases flow in my project. I face some problems in patch function? Actually, what is the function of patch? I welcome the responses from all of you. Thank You!

Use Patch after you've initialized to fill areas of your domain. So you can then start the solution with one part filled with water and another part filled with air, rather than having to wait for them to "fill up". It's quicker and more stable.

What are the values i need to patch? How about the values of velocity of x-axis, y-axis, z-axis and etc which appear in the command box?

With patch you are able to give an initial guess to your solution. Imagine a flow through an elbow (90 deg.) It wouldnt be reasonable to initialize the whole flow field with one initial guess for exaple in the x direction. Because after the elbow the mainflow direction is y so you can patch diffrent zones with diffrent velocities (temperature etc.)

Dear Marco,

I am not sure about what you mentioned. Let say in the case of 90 degree elbow, the flow is from -x axis to z axis. So how I going to define the patch value for the x, y, z velocity? Can you please explain it in detail? Thank you.

With Adapt Region you can create a so called register, just mark the zone you want to patch a velocity to.

Then you can patch a value under ->initialize->patch in teh fluent menu