[raunakjung]

I am doing a simulation of a fluidic oscillator.
In the experimental setup, one oscillator is mounted on a metal stand. Upstream of the fluidic oscillator it is supplied with pressurized air with a maximum pressure of 16 bars.A plenum is installed to provide homogeneous inflow conditions. The supply rate is controlled by a mass flow controller allowing a mass flow up to 28 g/s with an accuracy of 0.6%.
http://https://drive.google.com/drive/folders/0BzoaED8WwBOWamptZXJaa3dQS1U?usp=sharing

What boundary conditions should I apply for the simulation? I have used mass flow and static pressure outlet. But don't know how to apply effects of pressurized air.

Please help me understand this problem.

Thank You

[FMDenaro]

https://www.researchgate.net/publica..._viscous_flows

http://www.cerfacs.fr/~cfdbib/reposi..._CFD_11_31.pdf

[Marpole]

You can ignore the upstream air pressure (i.e. max 16bar) when you setup your model. That will over constrain your problem. If you measured the upstream pressure, it is a very good data for verify if your CFD model is correct and accurate.

[raunakjung]

Originally Posted by Marpole

You can ignore the upstream air pressure (i.e. max 16bar) when you setup your model. That will over constrain your problem. If you measured the upstream pressure, it is a very good data for verify if your CFD model is correct and accurate.

What will be the effect of upward pressurized air ? Do I need to change density at the inlet ? There is fairly a long inlet channel before the air reaches the nozzle .

[Marpole]

The effect is included in your model though you do need properly set the inlet density if it is asked. When I said it is included, I mean the flow rate is indirectly linked to the upstream pressure. If however, you apply pressure and flow rate at the same time, the model might not converge because the input pressure and flow rate might not accurately coherent to generate a stead state flow.

[raunakjung]

Originally Posted by Marpole

The effect is included in your model though you do need properly set the inlet density if it is asked. When I said it is included, I mean the flow rate is indirectly linked to the upstream pressure. If however, you apply pressure and flow rate at the same time, the model might not converge because the input pressure and flow rate might not accurately coherent to generate a stead state flow.

thank you for your reply. I carried my simulations at using mass flow rate and static outlet pressure and ambient density 1.189 kg/m3 but my results aren't matching with the experimental data. I could only think of the difference in density between the computational and the experimental case for such.

[Marpole]

It becomes very interesting when comparing CFD result with experimental data; this will make CFD practical and useful. What's the difference?