Learning Forum

[FaizanYounas]

Hi. I'm modeling

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[Rob]

What are you including in the model? Phase change and bubble expansion may require something else switching on. As an aside, /forum/discussion/23093/why-ansys-employees-dont-download-attachments

[FaizanYounas]

I'm using LEE + VOF to simulate bubble rise and condensation. The simulation is working well. But, I couldn't plot the graph of bubble volume with flow time. In my plot, the volume is shown constant but the bubble is condensing. Please ignore the report name "diameter" and the attachment.

[Rob]

Is there a value or is it reporting zero? Note, you've also only run for 0.006s so it may not have started boiling?

[FaizanYounas]

That was not the problem. Anyways, I figured it out. The problem is my bubble radius is 1.5mm so the initial volume should be 14.13. But, in the plot file, it is 7.06. I'm wondering why the volume calculation is wrong in the plot. Do you have any idea about this, Rob?

[Rob]

You're reporting the "volume" of the mixture in one fluid region. Set to report the volume of the gas phase in the both fluid regions.

[FaizanYounas]

Thank you for the reply. I have tried this too. But, the problem is still there.

[Karthik Remella]

Hello This is a 2D simulation. So, the volume is going to be pi*r^2*1 m (Fluent considers the depth into the plane as 1 m in the z-direction) and not 4/3 * pi* r^3.
Karthik

[FaizanYounas]

Ahh, I see. The problem is the research paper that I'm following performed 2D simulations and calculates the volume by 4/3*pi*r^3. Or, maybe they just multiplied by a factor of 2 after using pi*r^2. I don't know. Anyways, thank you very much

[Karthik Remella]

You are welcome!