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-   -   BC for rhoSimpleFoam (https://www.cfd-online.com/Forums/openfoam-solving/57770-bc-rhosimplefoam.html)

uli_u September 29, 2005 13:59

Hi, first of all thanks for
 
Hi,

first of all thanks for this great toolset!

I have finished to set up a case to simulate the steady compressible turbulent flow through a manifold (1 inlet, 1 outlet) with rhoSimpleFoam. The goal is to estimate the massflow through the geometry by specifying:

Inlet: Total pressure 1bar, Temperature 293.15K
outlet: Static pressure, 0.9bar

Everything seems be fine but I have still the problem of defining the right BC for this setup.
What should be specified at the inlet to reflect the above BC?

Thanks for any help,

regards
Uli

maritozzo September 30, 2005 06:51

Sorry.. How do you set the rho
 
Sorry.. How do you set the rhoSimpleFoam solver. I compiled it but i can't find it in the FoamX case window please help me

mattijs September 30, 2005 13:15

rhoSimpleFoam is probably not
 
rhoSimpleFoam is probably not configured inside FoamX.

You'll have to edit the files by hand. Just copy and modify an existing tutorial case for one of the other solvers.

uli_u September 30, 2005 13:47

Hi Muzio, I have edited the
 
Hi Muzio,

I have edited the files by hand and started the code. The informative error messages helped me to complete the configuration.

I will send you my example by mail. Just put your own mesh in, edit the BCs and start the run by calling rhoSimpleFoam <your_root> tube.

The mesh I put in is just an example, the code will die after a few steps.

Maybe you can help me to find out the BCs for my problem (Totalpressure inlet 1bar, static pressure outlet 0.9bar).

Uli

uli_u October 3, 2005 04:52

Hi, I have tried to create
 
Hi,

I have tried to create a FoamX configuration for rhoSimpleFoam. Just untar it under $FOAM_SOLVERS/rhoSimpleFoam which will give you the directory FoamX with all the files needed for your first steps with rhoSimpleFoam.

http://www.cfd-online.com/OpenFOAM_D...hment_icon.gif rhoSimpleFoam_FoamX.tar.gz

As I am very new to Openfoam, there might be some mistakes in there but hopefully there is some expert out there who will fine tune this...

Have fun,
Regards
Uli

uli_u October 3, 2005 06:44

Hi again, for those who are
 
Hi again,

for those who are interested I will add a test case for rhoSimpleFoam. It is a curved tube (meshed with netgen) with an inlet velocity of 50m/s, T=293.15K. Outlet pressure is 1bar. Create a directory under your tutorial directory, call it rhoSimpleFoam and untar the case there.

I have not finished to run this case, after a short time the calculation crashes. Neither decrease of the p-underrelaxation factor helps nor playing with the solver tolerances. Any ideas?



Regards
Uli

uli_u October 3, 2005 06:51

Sorry, the compressed size
 
Sorry,

the compressed size of the case is 1.5MB but the board posting limit is 50k. If you are interested, drop me a mail, I will send you the case.

Uli

mattijs October 4, 2005 05:04

Hi Uli, did you try underre
 
Hi Uli,

did you try underrelaxing rho? Just add an entry called 'rho' to the relaxationFactors.

maritozzo October 4, 2005 08:24

Hi everybody , first of all ,
 
Hi everybody , first of all , thank you very much!!..the last file was good.. but now i have other problems.
I have to calculate lift and drag acting on a airfoil, I'm using liftDrag application but it always give me strange results.
For example i always obtain drag coefficient zero for every angle of attack and the lift coefficent is given as a vector while it should be a single value

I just think that it refers to three directions because OpenFoam is a 3d code, but i don't know how to explain myself the drag coefficient

Thank you

uli_u October 4, 2005 12:54

Hi Mattijs, that was a good
 
Hi Mattijs,

that was a good hint! I looked into the code and saw the call to rho.relax...I should have looked earlier!

After using the factor for rho the calculation ran a lot more timesteps, but there seems still to be an open issue...it still becomes unstable.

By the way, do you know the default value, when I use no detailed specification for rho-underrelaxatrion, is it 1?

Regards
Uli

mattijs October 6, 2005 15:15

Hi Uli, I did not converge
 
Hi Uli,

I did not converge it fully but it seemed to work with a really low underrelax for k,eps,rho (say 0.05)

Might just be that I haven't run it enough though.

uli_u October 9, 2005 14:16

Hi Mattijs, thanks for this
 
Hi Mattijs,

thanks for this information. I tried it and the job ran for a long time without getting unstable. I also stopped it, there was no real convergence. I think the problem itself is not a good example, I will think about a better one, maybe using a hex grid.

Nevertheless I still have the feeling that there is something wrong with the turbulence BC - especially epsilon. In several calculations I experienced that using "zeroGradient" works much better than putting a fixed value of epsilon on the inlet. I will investigate this in more detail and collect some pictures showing this behaviour.

Regards
Uli

giovanni May 29, 2007 12:33

Hi all, can anyone send me
 
Hi all,

can anyone send me Ulrich's test case for rhoSimpleFoam?
The one mentioned on Monday, October 03, 2005 - 04:51 am?

Thanks a lot in advance!

Giovanni

braennstroem July 11, 2007 05:47

Hi all, I would like to tak
 
Hi all,

I would like to take a look at the test case, too! Is it possible to get a small piece, without the mesh!?

Regards!
Fabian

lgriffiths December 15, 2007 13:38

hi could somebody email me
 
hi

could somebody email me either the above rhoSimpleFoam test case, or just any test case (for rhoSimpleFoam).

mesh is not important.

this would be a huge help, and much appreciated!

cheers,
Laurence

jphandrigan February 10, 2009 15:24

Are there any test cases kicki
 
Are there any test cases kicking around for rhoSimpleFoam? If there are, I'd greatly appreciate it if someone could it to my email address at jhand085@uottawa.ca . Thank you in advance!

hellorishi March 13, 2009 10:30

Hello Everyone, Even I am i
 
Hello Everyone,

Even I am in the same boat...
There is no tutorial for rhoSimpleFoam in 1.5 or 1.5.x and I would like to have an example to understand the working BC,system, constant etc.

If anyone has a please help.

THanks
RIshi

kcjarvis56 March 14, 2009 23:09

Rishi, Drop me an email at kc
 
Rishi,
Drop me an email at kcjarvis56 at hotmail(dot)com and I will send you a case.
Kirk

hellorishi March 17, 2009 10:50

Thanks Kirk,

The case is now converging !

mihir1310 April 2, 2009 16:43

hello

may i have the test case for rhoSimpleFoam ??




thanx & regards !!!!!!!!!

mahaputra May 27, 2009 16:38

Quote:

Originally Posted by kcjarvis56 (Post 201174)
Rishi,
Drop me an email at kcjarvis56 at hotmail(dot)com and I will send you a case.
Kirk

Dear Kirk Jarvis & Rishi


would you share your rhoSimpleFoam case to me as well? please

my email addres is : nugroho.adi.s [at] gmail.com


Thanks

Nugroho Adi

RachelElizabeth June 1, 2009 00:57

Hi all,

I am in the same boat too. Is it possible that someone could send me on the test case - my email is
rachel.harch@gmail.com

many thanks
rach

smart October 13, 2009 14:05

I would like to have an example for rhoSimpleFoam
 
Hi all,

Can I have the case to see how to implement the boundary condition and to have a example for the rhoSimpleFoam solver? My e-mail is sylvain.martel2@usherbrooke.ca

thank you very much.

Sylvain

smart October 27, 2009 15:01

Temperature problem
 
Hi, I have a problem using rhoSimpleFoam with my own case. I want to simulate a gaz flow in a converging-diverging nozzle. The inlet condition are: T=573K, P=10e5 Pa, U=pressureInletOutletVelocity. At the outlet, only the pressure is known (P=9.85e5 Pa). With these conditions, the solver stop after 8 iterations.

If I put the temperature in the range of 1 to 5 K, the solver work well, but I don't know why T>5K is not OK! Do you have ideas?

Thank you very much,

Sylvain

Pat November 4, 2009 07:17

hallo everybody,
may i have the test case for rhoSimpleFoam? my E-mail ist assogbapat@hotmail.de or toupador@googlemail.com.
thanks and regards

bernarde November 9, 2009 08:40

Hi all

Wouldn't it be possible to upload this tutorial case to a server that everybody can download it?

mhmt January 20, 2010 10:14

rhoSimpleFoam
 
Hi. Can I also ask for the test case of rhoSimpleFoam ? It will be of great help. I need to use this solver for a steady, transonic flow simulation. Please save me, thank you very much...

My e-mail : mehmetkaya84@gmail.com

mihir1310 January 20, 2010 14:12

Quote:

Originally Posted by mhmt (Post 243173)
Hi. Can I also ask for the test case of rhoSimpleFoam ? It will be of great help. I need to use this solver for a steady, transonic flow simulation. Please save me, thank you very much...

My e-mail : mehmetkaya84@gmail.com

sent........

bernarde January 21, 2010 02:02

Hi

Please could I also have the test case - it would be much appreciated.

My email is bernard.esterhuyse@gmail.com

Best regards

smart January 21, 2010 09:04

I will send it to you by e-mail...

Sylvain

martino January 26, 2010 04:14

could anyone send me the testcase too?

ma.sonntag @ gmail.com

thanks alot in advance.

smart January 26, 2010 09:17

I will send it to you.

Sylvain

mihir1310 January 26, 2010 12:18

Sylvan

Looks like you already sent the test case .. Thank you

SunnyPP January 28, 2010 13:04

Request
 
Hi,

Could anyone send the test case to me as well?

My email is shogo.takeda.ldn@gmail.com

Thank you

mihir1310 January 28, 2010 13:05

^^^sent ...

puhulie February 4, 2010 09:00

RhoSimpleFoam
 
Hi everybody - like all the others here I'm lacking of rhoSimpleFoam-Help. Could anybody send me the case to juliepuhulie@gmx.de ? Thanks a lot !!!

smart February 4, 2010 09:24

I will send it to you in a few seconds... let me know if all is OK!

Sylvain

puhulie February 4, 2010 10:01

thx
 
Thank you very much, Sylvian! At least I have something to start now with. I will see whether those cases can answer my questions. Regards puhulie.

dominicd March 12, 2010 09:16

Hi there. Could anybody sent me the File as well, please?! dominicd@gmx.de Thanks!

Fabio_77 March 12, 2010 10:22

hello

may i have the test case and help-files for rhoSimpleFoam ??




thanx & regards.

Fabio


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