Resilient diaphragm

[johanmyburgh]

Good day

I want to know if Autodesk CFD can do a simulation with flow through a valve that has a rubber/elastic diaphragm. The inlet pressure will affect the deformation of the diaphragm. This diaphragm "chokes" the outlet flowpath and thus affects the pressure drop over the valve.

Also, can CFD take a table of inputs to simulate the design at many different input pressure and flows without having to change each parameter by hand after each simulation?

Thanks in advance

[karol.suchon · Accepted solution]

Hello Johan,

In Autodesk CFD we have a motion analysis that could compute the fluid-structure interaction and move the object inside the simulation but volumes are the rigid body so any deformation could not be computed. If you could apply the diaphragm as a rigid body it should not be a huge problem to do it.

 We do not have a table of input or any other feature which could create the scenario with the different values as a boundary condition, we could achieve something similar using the previously prepared script.

If you have any other questions, feel free to ask.

Best regards, 

Karol

[apolo_vanderberg · Accepted solution]

Karol outlined this well but to add a couple additional items to think about.

If what you care about is the fact the diaphragm chokes flow at a certain pressure while you make design considerations to other portions of the geometry - you could model the diaphragm as a distributed resistance that uses a Head Capacity curve to mimic how the pressure drop changes in the diaphragm based on the upstream flow. 

For the table of inputs, with our Python api, you could have it read the data and update cloned Scenarios as needed. 

[marwan_azzam · Accepted solution]

Hello @johanmyburgh ,

To add to what Karol and Alolo said, you will need another structural analysis FEA package such as Inventor Nastran or Fusion360 simulation to model how the diaphragm would react (deform) under a certain pressure.

You can run the CFD analysis and calculate the reaction forces on the diaphragm.  At that point you can use those forces as loads in your structural analysis to see how much a certain flow will deform the diaphragm.

Marwan