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kkpanayotov April 15, 2012 16:45

Several continueus fans in a long tube SwFlo
Greetings to all,
I have a question regarding a big model ( 800 meters long) which i am thinking of making a simulation of it .
The simple model for the simulation will include a wind tunnel of around 800 meters , intake from one side, outtake on the other, AND Several Small Fans ( only on the top side of the tunnel ) located in different distances from each other .
The whole idea is the air taken from the intake to pass through the fans and to see how the intake air is moved through the tunnel.
I started testing the idea with but the insert of "Internal fan" as an option does not take anything at all from the intake side and only gives to the Outtake side.

Have some one faced this issue ? I will be grateful for any comments...

JosephKim April 23, 2012 23:20

I think you should use "local rotate" method than "Internal fan"..

I can't explain in detail but if you teach me your e-mail address, I can send a material related to "local rotate" method.

kkpanayotov April 24, 2012 01:15

You have got a PM...

JosephKim April 24, 2012 01:37

PM? Patent?
I don't understand.. Anyway this material is released for everyone.

kkpanayotov April 24, 2012 02:26

PM = Private massage
Sorry for that...

JosephKim April 27, 2012 02:30

I didn't know private massage function.
I sent a e-mail. Good luck.

Boris_M May 4, 2012 15:59

I think the problem with your internal fan is that internal fan doesn not mean you have to use this fan in an internal analysis.
The internal fan is for a fan that sits in somewhere in the calculation area and has two faces to the fluid around it, one is sucking the air in the other is blowing the air out. If you want to use a fan on your inlet, then it is an external inlet fan as the fan is mounted externally and blows the air into the fluid region. For the external outlet fan it is also mounted externally but is sucking the air out. so just like an inlet or outlet condition.
But if you have the fan geometry and want to really see how the air is moving around the blades of the fan you should go with the local rotation as Joseph says.


kkpanayotov May 4, 2012 16:06

Thanks to all..
The idea is that inside the computational domain , there is an fan, which i don't have any data regarding it's geometry except that i know the fan inlet/outlet speeds...
That is why i wanted to know if someone has faced this problem.
Yes i can make a model of the fan and make it work with rotation until i reach the speeds that i know, but still i wanted to know if there is a way around that ...
Thank you ..
If you have any idea regarding this "way around" i will be greatfull to get it posted...


Boris_M May 4, 2012 16:09

Well for this fan you would need the fan curve as it depends on the pressure difference between the two sides of the fan. If you have that data from a datasheet you can simply create your own fan curve with that data and use that.


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