topic Re: Simulating hollow section free surface filling in CFD Forum

Simulating hollow section free surface filling

Anonymous — Sun, 14 Jun 2015 18:19:43 GMT

Hi,
I am a student and I am willing to simulate the filling of a hollow pipe handrail, and its filling time (If ever you were wondering; its a simple simulation for when doing galvanising).
I have drawn the handrail using Frame Generator. I have also made holes where the pipes would not have access to the fluid (So that galvanising is done everywhere). Did a reservoir representing the volume present in the bath and connected it to the handrail.
Problems:
1. I can't fill the void successfully there is a thin layer in front of the cross-section where I used to fill void.
2. Which boundary conditions if any should I use? N.B I am using Height of Fluid in Initial Conditions on the reservoir part
3. For free surface I have set the gravity, but how could I make the animation second by second, what "Time Step Size", and in save intervals "Results", "Summary" should I set?

Thanks.

Regards,
MUSTUN Sultan

Re: Simulating hollow section free surface filling

Jon.Wilde — Mon, 15 Jun 2015 12:05:22 GMT

Hi,

I tend to add solid blocks to the inner diameter of the parts in CAD. This seals the model and CFD will just auto-fill it when you launch
It sounds like you don't need any boundary conditions if this a reservoir draining. If you know the flow rate though, remove the reservoir and just apply a flow rate - it would be quicker to solve
Use the default solver settings - then save intervals based on seconds - we tend to save no more than 30-50 or so steps per analysis. You could set this to 1 and CFD would save you a result every second.

Hope that helps,

Jon

Re: Simulating hollow section free surface filling

Anonymous — Mon, 15 Jun 2015 16:19:49 GMT

Hi,
Thanks for the quick reply.

I have tried the solid way it works like a charm, but I am having problem with the animation part, it is only showing one to select to "animate"
Could you please chek the attached photo and tell me which value has to be changed, so as to have it second by second.

Regards,
MUSTUN Sultan