Force Air Plenum Design for Electronics Enclosure

[Mechie10]

I am looking for plenum design guidelines for electronics enclosure with forced air cooling using axial fans. Operating conditions are -5 to 55 C, 1000 ft below sea level to 6000 ft above. Of main interest is distance from fans to allow uniform flow, but overall dimensions and other information also needed

TIA

 

[Montemayor]

Mechie10:

You say you are looking for guidelines. Yet you specifically ask for "distance from fans to allow uniform flow, but overall dimensions and other information also needed". Aren't you asking for details on a specific design?

If you are not able to do the design yourself (what your query seems to point out), how can you expect others to do it for you on a forum? We can answer or comment on any heat transfer problem you might be undergoing; however, the inability to design a heat transfer problem is not a "problem". It amounts to a shortcoming that should have been resolved with sufficient engineering heat transfer courses. This forum will help you; we've demonstrated that sufficiently in the past. We can't be expected to do your design - particularly when you don't furnish all the design basic data and the scope of work.

Don't take this as harsh criticism - which it's not. My point is that you can't reasonably expect what you are asking of this forum and plan to use it it in a formal design package. That's not what this forum is for.

 

[Heckler]

Mechie,

Here is a website that might be of some help

http://www.coolingzone.com/

They have a lot of white papers on design. Best of luck

 

[sreid]

Buy or borrow (library, inter library loan) the following book

http://www.amazon.com/exec/obidos/t...f=sr_1_3/002-8789772-0440016?v=glance&s=books

This book is practical and take you through paper design of exactly the kind the design you are doing.

 

[Tunalover]

Michie10-
As a general rule, air upstream of the fan should be given a one fan diameter distance so that a healthy velocity profile may develope (admittedly, most designs don't tolerate this rule of thumb due to space constraints). Likewise, before encountering obstructions, turns, or constrictions, there should a one fan diameter distance downstream of the fan for the same purpose. As for losses due to turns, constrictions, etc., I have found that unless your design is exceedingly simple, it is a fruitless exercise to try to obtain the static pressure curve with hand calculations. Normally a CFD program can be used but it really depends on how much you need to know. You can also send your prototype out for testing. There are many test labs that will provide you with the static pressure curve.

As indicated, full characterization of an air-cooled enclosure is no "walk in the park." You may want to get someone to help you who has done it before and validated their predictions by test.


Tunalover