Learning Forum

[ZX]

I am trying to do something about 2-way FSI. When I am using the 'Transient structural' and 'Fluent', there is no problem to have a 2-way FSI, because I can link 'Transient Structure' and 'Fluent' to the 'System Coupling'.

However, when I start to do the same thing with the 'Harmonic Response', it doesn't work. Although I can still link 'Fluent' to the 'System Coupling', but I can't link the 'Harmonic Response' to the ''System Coupling'. In this way, how can I use the 'Harmonic Response' for a FSI simulation?

Thanks in advance.

[Stephen Orlando]

Connecting Harmonic Response to System Coupling isn't possible.
Can you describe the application? I or someone else might be able to provide recommendations.
Steve

[ZX]

Hi Steve, thank you very much for your reply, and yes I will describe more details about my model.
My model is about 2-way FSI. The model is a hollow cylinder, and there is a plate (with a very small orifice) in the middle which separate the hollow cylinder into two parts, like figure 1 and figure 2 shown below. The hollow cylinder is fixed, and the rim of the plate is fixed, but the other parts of the plate are free. For example, the center of the plate can move up and down.

At beginning, the upper part contains water & air, and the lower part contains air, and mixed water & air near the orifice, like figure 3 shown below (in figure 3, the red is water and blue is air, it is a contour of Volume of Fraction of water). If the plate keep static, because of surface tension, the water will not flow into the air through a very small orifice, like the figure 3 shown below.

When the plate starts to vibrate (the rim of the plate is fixed, but the plate center can move), especially the plate moves up, the water is going to be 'filtered' by the orifice to form a droplet and flows into the air. For this process, I need VOF method and Patch in Fluent.
For the plate vibration, if I apply force or displacement on the plate, there is no problem because I can use 'Transient Structural Analysis' to do this, and then couple 'Transient Structural' with 'Fluent' to do this 2-way FSI, like figure 4 shown below. In figure 4, the plate moves up, and more water is filtered by the orifice. (there is no droplet formation because of the unsuitable Boundary Conditions, but at least I can use Transient Structural and Fluent to couple).

However, currently, this plate is vibrating in a Harmonic Response Way, which means I can only simulate the vibration of this plate in 'Harmonic Response Analysis'. Therefore, the result is, I find that I can't couple the 'Harmonic Response' with 'Fluent', so I have no idea about how to do this 2-way FSI simulation.
In this way, could you please tell me if you have some recommendations? Thanks in advance.

[ZX]

Hi Steve Could you please tell me if you have any recommendations about this application? Does it mean the only way is to transfer the Harmonic Response to Transient Structural?
Thank you.

[Stephen Orlando]

I'm not really sure what you mean by "transfer the Harmonic Response to Transient Structural?"
From what I can see, using Transient Structural coupled with Fluent is your only option.
Please see this tutorial for an example, https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v202/en/sysc_tut/sysc_tut_oscplate_wb_fluent.html
Steve

[ZX]

Hi Steve Thank you for your reply.
"Transfer the Harmonic Response to Transient Structural" means that I am using 'Harmonic Response' to simulate the vibration plate, however, I can't couple 'Harmonic response' with 'Fluent'. But I can couple 'Transient Structural' with 'Fluent'. So I am thinking for this plate vibration, is it possible to use 'Transient Structural' to replace 'Harmonic Response'? If I can use 'Transient Structural' to get the same plate vibration, then I can couple 'Transient Structural' with 'Fluent'.