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Rob February 6, 2009 09:41

Fan Boundary conditions with external analysis
Hi all,

I am new to Floworks and have run through the various tutorials but I am having a real problem trying to run an analysis on my own models!

I have what is efectively a sheet metal chassis with an internal fan and lots of air vents. I was told by an expert during my training that I can run an external analysis and then not have to worry about creating boundary conditions for all my ventalation holes and also the main reason is that with sheet metal I don't have a true internal volume bacause of the way that the corners mate etc, ( lots of gaps etc). The problem is that I cannot add the fan because it tells me that it does not lie on a boundary regardless of whether I choose an internal or external fan. I have obviously created a seperate part for the fan which I have positioned into one of the sheet metal walls, as I normally do with an internal analysis. How can I get around this without having to suppress lots of vents and try to seal the chassis? I would really like to know because I cannot move forward until I know. Any help would be greatly appreciated. I have run several custom internal analysis without any problems, but when the chassis is very complex like this there must be a way to bypass building parts for boundary conditions.

Kind regards,


M February 10, 2009 01:04

Re: Fan Boundary conditions with external analysis
Hi Rob

Do you set your analysis type as external? If yes, have you tried to use 'check geometry' to see if all the solids and the fan is picked up correctly?

In this case you can use an external fan, just make sure that you choose the correct faces for 'from fluid to fan' and 'from fan to fluid'.

Regards, M

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