Learning Forum

[gindi]

Hello,

As can be seen in the attached image, the pipe outlet is initialized with air even if i set the whole domain as water (setting water volume fraction = 1). I tried patching also but with no luck.

The outlet boundary condition is set to mass outlet flow with air mass flow = 0 and water mass flow = 22 kg/s.

[Rob]

What did you set the initial volume fraction as, and what zone/register did you patch?

[gindi]

I tried:
1) setting the initial volume fraction for water = 1, and patching air region as water volume fraction = 0.
2) setting the initial volume fraction for water = 0, and patching water region and pipe region as water volume fraction = 1.
Both ways gives the same result.
The odd thing is that I have a similar model but without the floor slope that doesn't have this issue. I tried reconstructing the geometry again as I though i might have missed something but still the same issue persists.

[Rob]

Can you check the boundary labels and cell volumes to make sure the zones are as expected? If the other model works I wonder if you missed a volume when setting labels.

[gindi]

I did that actually. Exactly the same as the one I had earlier. Three fluid zones named as I mentioned earlier, and the boundary conditions set similar to those I had before.
I will give it another try and rebuild the whole model again as a recheck. I will keep you posted.

[Rob]

Can you check you patched the correct fluid domains? The obvious hiccup is not patching the top cylinder.

[gindi]

I understand your reasoning, but this should not be the case if I initialized the whole domain with water volume fraction = 1. Then patching the air region, where the pipe is not part of it.

Any way, I reconstructed the whole geometry for the third time and remeshed it again. now it seems that the issue has gone. I will try to debug it step by step and compare with the old problematic one to check again where I went wrong.

Thanks for your support.