fan boundary condition
 

hi ,everyone
does anyone uses the "fan boundary condition" in Fluent software? I need some help in setting the parameter.
any help will be appreciated
wish all of you
This is the first time that I ask a quesion here,my English is not so well,wish you will unstand me well.:p

any help will be appreciated.Thanks

if you can send me your email id i can send you a notes on how to set up the boundary conditions for the jet fan in fluent

cheers

Ravi

Hi ,Ravi
Thank you very much for your reply. My email address is blusius@126.com. I am looking forward for your email.
Thank you again

hai.. im also has same prolem to set up 3D fan.. can u help me?

hi,
you can simply define a volume domain and in fluent change it from interior to fan. then set the pressure gradient between two sides of fan and swirl velocity(in 3-d) of rotating fan. then solve and see the results!
yours,
mohammad

I have no idea about how to set the swirl velocity which contains two component: radial velocity and tangential velocity...can u help me?

I only know something about the fan which is supposed to be static in the flow field. if your model is supposed to be swirl in the flow, i do not have much idea about how to set the parameters which are needed by Fluent Solver

hi,
I'm not sure but I think you can only set tangential velocity in fan models, not the radial. and the tangential is usually set as the rpm of the fan (propeller,turbine,compressor,...). if I'm not wrong, fluent uses pressure gradient as a pressure jump between two sides of fan zone and adds swirl velocity as V_theta=r*w to the flow. the result should not be so wrong but you know it's just an approximate!
yours,
mohammad

thanks to all.. actually my problem since at Gambit.. Fan is a part of my model.. I try a few method like subtract and split fan from flow field then set up bondary condition.. I dont know ist my problem at modelling or set up boundary condition in gambit.. Please help me..

Jet Fans BCs Notes
 

I need the mentioned notes too so, please send me them on eng.sherifgomaa@gmail.com

Thank you for your help

Sherif

halo.. may i have the notes that u mention above..? i do appreciate it.. my emel is harmaizura90@gmail.com

in the ansys fluent help pdf file , there is a very detailed description of the fan model in the flug.pdf .

good luck !

Hello ! I know it's a really old post. But by any luck, can I have also the note on the fan model please?
Thank you very much

please send me your email id. I will see if i can find it for your and send it across.

Regards,

Ravi

Hello. Thanks for your reply ! My mail is: guillaume_dlvm@hotmail.fr

Greetings;

I´m working on a project in which I have to analyse the flow over a spinning propeller and a cylindric body behind it, I would be really thankful if you could share those FAN notes with me as I was told this Boundary condition could be helpful to my model, thus I´m trying to learn as much as I can about it to model my case.

My email is s.gkrlos@hotmail.com

hello i need to simulate jet fans can ravi please send me the note too my email is jgd05@mail.aub.edu

Fan model
 

Hey Ravi,I am modeling a water tunnel with a fan in it. I have already tried to use the tangential velocity and pressure jump as inputs without being successful. I will be very thankful to you if you send me your fan model to fjodor.arndt@web.de. Thank you in advance.
Cheers

this is old topic.ı feel lucky.ı want to learn how to analisy and simulationabout centrifugal air fan.is there anoyone to help me by sending notes,video models.thank you so much for interest my gmail adress is murat.akarsu44@gmail.com

Notes
 

If anybody have these notes please email them to angrula@gmail.com

This is just a summary on fan boundary condition.
1. You need an interior boundary between two cell zones not interface. It means that the mesh must be conformal over the surface that fan is supposed to e implement.
2. Easily switch the boundary condition from 'interior' to 'fan'.
3. Now you can set the fan parameters. You can start with constant pressure jump to be sure about the direction of the fan.

Fan BC is a 2-D surface. To model 3-D fan e.g. centrifugal fan, other approaches are needed.

Notes
 

If anybody has the note, can email me? I will be very grateful... my email id: ttaru.me07@gmail.com

Fan boundary condition unexpected results
 

Hi,
I am using the fan boundary condition is FLUENT.

I would like to know:
1)Which pressure (static or total) is the one that you specify when setting up the case?
2)Does the total temperature change across the fan?

Please, if you know the answer offer me some help.
Also I would appreciate if anybody could send me the "fan" notes. My email is: crespoa.javier[AT]gmail.com

Thanks!!

The fan boundary condition is supposed to model an axial fan.
1. The specified pressure jump is static.

Thanks. However, total pressure also changes across a fan.

I ran a calculation in which I specified a pressure rise of 20kPa in the fan boundary condition menu. Looking at the results by doing "Surface integrals" of static pressure and total pressure just before the fan and just after the fan" (both area-weighted and mass weighted offered similar results) the static pressure rise I got was 23.8KPa and the total pressure rise I got was 21.3 KPa. It was an inviscid calculation and the "ideal-gas" model was used to model the air. The SIMPLE scheme was used and 2nd order methods were employed. I refined the mesh (but only in the near fan region) and the results I got were the same

As you can see, neither of the pressure differences matched what I specified and even the difference in total pressure was closer to the specified value of 20 KPa. What do you think?

Total pressure by definition is the sum of static and dynamic pressure. Dynamic pressure is rho*v^2/2. So, if the velocity does not get changed, the dynamic pressure would be constant for incompressible simulation on both sides of the fan. In the other word, if your simulation is incompressible, then the dynamic pressure won't change unless the cross sectional area changes on both sides of the fan.
Run your simulation for many iterations. According to the cases that I ran, it takes long time for the pressure jump to converge to specified value.
Although the values that you mentioned are close to 20, you can test cell based and node base methods. Sometimes, it makes difference.

Simulation of hollow pipe with tool in it
 

Hey Guys,

I need help with something. I hope somone can help me. Its my thesis and am stuck in it.:confused::confused:

It is a hollow pipe with a spherical tool in it. Fluid enters the pipe from one end and exits the other way. The tool has a dia of 282mm. the ID of the pipe is 303.24mm. i have done some simulation but i want to know if it is right. I am getting so confused with the setup. I want to find the change in pressure across the pipe. I tried attaching the Ansys fluent folder but its too big to be attached here. My email id is mohamed.shabir92@yahoo.com.

Can anyone pls help me with it or send a mail so that i can send u the files. Thanks in advance.

And i am so dumb i do not know how to post this question in a seperate topic. Struggling a lot

Thanks for your response. The fluid under study is air and I model it as an ideal gas, so the density can change. My domain is a 2-D rectangle. At the inlet I specify aa total pressure of 100KPa, I choose 20KPa for the pressure jump in the fan boundary condition menu. Finally I specify an outlet static pressure of 110KPa. When i look at the results(converged to 10^-6 of residuals) the Mach at the inlet is
0.529 while the Mach at the outlet is 0.389, so velocity changes.

I ll try your suggestion.of node based approach. Does anybody else have other ideas?

fan boundary condition
 

Hi!!!

If anybody has the note, can email me? I will be very grateful... my email id:

mattia.delfavero@gmail.com

HI, could I have the file?
Thanks
michele.roffi@hotmail.it

hello ravi,

i hope i can also get your notes on boundary conditions of jet fans.
driverwreckless@gmail.com is my email.
thanks.

Help
 

cheers

Ravi
I need the mentioned notes too so, please send me them on Mohamed.elkhial2011@gmail.com

Thank you for your help

Sherif
Gomaa, Sherif is offline

Fan Model
 

Hello
can I have also the note on the fan model please?
My E-mail: lusanchezrivera@gmail.com

Thank you very much

Can anyone just share the notes here? I appreciate it.

anyone has the notes please?

yankicob@gmail.com

Hello Ravi, I am working on the similar problem. If possible can you give notes related to it? Thank you

Here is my mail address: kailasmuke37@gmail.com

Can anyone send me the notes my email is rrdop@uol.com.br? I working with a car radiator and i think i'm setting something wrong beacause the flow dont go out from my fan zone. Do someone knows what i have to do? :confused:

Hello everyone,

Can anyone please send me the Fan notes? My email id is chetankishore@gmail.com

hello, can anyone send the notes about fan boundary condition?

matteo.capozucca at gmail.com

thank you very much