How can I model a perforated plate using porous media/porous jump in FLUENT?

Time4Tea · July 26, 2018, 14:39

Hi, I am looking to simulate compressible internal flow through a valve in FLUENT, which includes a diffuser, which comprises a plate that is perforated with hundreds of small holes.

I am wondering if I can use either the porous media cell zone condition or porous jump boundary condition to model this. I have been reading through the user guide/theory guide for the porous media, and the main thing I am concerned about is whether this approach would correctly model the choking effect of a compressible flow. It appears that I would have to input coefficients that relate the pressure drop across the media to v and/or v^2; however, in a choked flow, v would be limited and would not change beyond the critical pressure drop.

So, can anyone tell me what the best way is to do this in FLUENT? Is the porous media/jump the right way to go?

Thanks in advance.

LuckyTran · August 3, 2018, 17:17

The choking effect can somewhat be accounted for by using the right porosity and enabling the superficial velocity formulation. This way, the faster velocity between the pores is simulated.

The D-F coefficients for the pressure drop are for major losses, which are frictional in nature and different than the pressure difference across a shockwave. I would consider using 0 for the D-F coefficients.

July 26, 2018, 14:39	How can I model a perforated plate using porous media/porous jump in FLUENT?	#1
Time4Tea Senior Member Lee Strobel Join Date: Jun 2016 Posts: 133 Rep Power: 10	Hi, I am looking to simulate compressible internal flow through a valve in FLUENT, which includes a diffuser, which comprises a plate that is perforated with hundreds of small holes. I am wondering if I can use either the porous media cell zone condition or porous jump boundary condition to model this. I have been reading through the user guide/theory guide for the porous media, and the main thing I am concerned about is whether this approach would correctly model the choking effect of a compressible flow. It appears that I would have to input coefficients that relate the pressure drop across the media to v and/or v^2; however, in a choked flow, v would be limited and would not change beyond the critical pressure drop. So, can anyone tell me what the best way is to do this in FLUENT? Is the porous media/jump the right way to go? Thanks in advance.

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August 3, 2018, 17:17		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,747 Rep Power: 66	The choking effect can somewhat be accounted for by using the right porosity and enabling the superficial velocity formulation. This way, the faster velocity between the pores is simulated. The D-F coefficients for the pressure drop are for major losses, which are frictional in nature and different than the pressure difference across a shockwave. I would consider using 0 for the D-F coefficients.