drag coefficient computation on a porous jump???

July 17, 2006, 23:13

Hi everybody,

In my study case I've got a porous jump to model a perforated plate and I would like to compute the drag coefficient on it. The problem is that Fluent only calculates the drag coefficient on boundaries declared as a wall (not as a porous jumb). Any idea to solve this problem???

Many thanks,

Fab.

July 18, 2006, 05:10

You can calculate the total force on the porous jump by integrating the pressure difference over the surface. The best way to do this is by using custom field funcions. Use the reference values to convert the force to a coefficient.

July 18, 2006, 09:27

Hi Vincent,

OK for the method, Thank you very much for your advice.

Cheers,

Fabrice.

wxn · June 5, 2017, 05:39

Hi,
may I ask a question ? How to integrat the pressure difference over the porous jump by using custom field funcions?

KaLium · June 5, 2017, 06:30

Don't overthink this problem.

You can monitor pressure on both sides of the porous jump. Then you can calculate the pressure difference yourself.

July 17, 2006, 23:13	drag coefficient computation on a porous jump???	#1
Fabrice Guest Posts: n/a	Hi everybody, In my study case I've got a porous jump to model a perforated plate and I would like to compute the drag coefficient on it. The problem is that Fluent only calculates the drag coefficient on boundaries declared as a wall (not as a porous jumb). Any idea to solve this problem??? Many thanks, Fab.

July 18, 2006, 05:10	Re: drag coefficient computation on a porous jump?	#2
Vincent Guest Posts: n/a	You can calculate the total force on the porous jump by integrating the pressure difference over the surface. The best way to do this is by using custom field funcions. Use the reference values to convert the force to a coefficient.

July 18, 2006, 09:27	Re: drag coefficient computation on a porous jump?	#3
Fabrice Guest Posts: n/a	Hi Vincent, OK for the method, Thank you very much for your advice. Cheers, Fabrice.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Plot drag forces at porous jump boundary condition	Shim	FLUENT	1	June 5, 2017 05:31
Am i right? porous jump drag force	Shim	FLUENT	2	August 25, 2014 10:33
Physical significance of porous jump coefficient	ulalala	Main CFD Forum	0	September 16, 2010 03:45
Automotive test case	vinz	OpenFOAM Running, Solving & CFD	98	October 27, 2008 09:43
Porous Jump : Drag Force	pk	FLUENT	0	May 15, 2008 08:39

June 5, 2017, 05:39		#4
wxn New Member sofina Join Date: Jun 2017 Posts: 9 Rep Power: 9	Hi, may I ask a question ? How to integrat the pressure difference over the porous jump by using custom field funcions?

June 5, 2017, 06:30		#5
KaLium Senior Member Kal-El Join Date: Apr 2017 Location: Finland Posts: 150 Rep Power: 9	Don't overthink this problem. You can monitor pressure on both sides of the porous jump. Then you can calculate the pressure difference yourself.