Air flow for commercial four way diffusers !?

[deluxairhead]

Hi guys I'm developing a new four way commercial 595 x 595 mm TBar diffuser and looking into spec's on other products out there and I have to say there ain't that much that i can find really so I guess most of the products ie : four way diffusers are just getting dropped onto any market place with little or no info on how efficient they are or aren't right !!

My question, being that I'm not an engineer : average air flows in :
200mm/8", 250mm/10", 300mm/12",350mm/14", 400mm/16" and 450mm/18"
flexi duct.......???

I've worked on an average of 350 l/sec supply, how does that sit across the board, as of course there's many variations to supply air !

What I understanding by my 30 years in this industry is, engineered systems of course they heat and cool spaces, these spaces have many unknown variables ie; people position, interior fittings, desk, chairs, partitions ect, these have a bearing on air flow and differ between client requirement, people refit interiors and move things around so this changes air movement in these spaces considerably.

So my design takes into account cold air falls, hot air rises, wheres my happy medium ?
45 deg projection out of diffuser face maybe ?

Any ideas would be very helpful, than you for your time.....

Regards Wayne Neylan/Deluxair

[Brian_UK]

Looking at your products it appears that you use the same as everybody else so must have all the design data already available to you.

Not being 'an engineer' must make designing an engineering product a bit difficult.

Cold air falls or hot air rises; it all depends on where and how you blow it.

[Tesla]

Hi deluxairhead
I like your innovation. You could incorporate mechanically temperature dependent angles. Also some method to restrict various areas and increase others for high load areas and where they tend to blow (sometimes) onto a work station.
But most of all get rid of some of the turbulence before the outlet grill, maybe you could curve the grill and streemline from the flexi. On another note I think round is better than square.
These are just some ideas for you to play with so let us know what you are toying with and what you think.

[Tesla]

OK I just had another idea when I went for a leak. How about as an additional optional extra something that would work like a garden sprinkler system that would create a gentle breeze which moves around. It could fit just inside where the flexi connects and use a little of the pressure/flow power of the air to rotate. Not too much though we wouldn't want to mess up any of those pretty ladies new hair doo's lol.

[deluxairhead]

Hi Brian
In replying to your comment, this is a totally new style of product ( diffuser ),I'm developing here, yes as another put it better round than square, it is round also.
Its a new form of production as well, this product is designed to perform in heating or cooling mode ( balanced ), it can also be configured design wise to be made in a predominant cooling style or heating style so in saying this please feel free to advise or comment on the above.
I'm interested to know your thought's being a man of 8,341 or so post's, you must have some vast experience to comment on this post, do tell !
Regards
Wayne Neylan / Deluxair

[frank]

There are numerous grille manufacturers in the UK who publish technical data on their products:
http://www.gilbertsblackpool.com/products.aspx?type=Grilles&1=1
http://www.scottaire.co.uk/
http://www.fnwairdiffusion.co.uk/airtransfergrilles.html
http://www.troxuk.co.uk/uk/

etc, etc.

These manufacturers have sizing nomograms for their products, and I think you are trying to re-invent the wheel.

Also, it would be appreciated if you would remove your company name from your signature....free advertising is NOT allowed on this forum, under any guise. Read the Rules http://www.refrigeration-engineer.com/forums/misc.php?do=showrules

[Magoo]

I have a huge preference for round diffusers, with the diffuser plate adjustable. The real problem is the plenum box supplying the air. The bit no one sees, generally cheapest possible and side entry, so all air goes out one side of diffuser. If you can master that, you are onto a winner. A diffuser and plenum box combination with tuning vanes etc., with low head clearances.

[deluxairhead]

Evening Mr Frank Mr Magoo

I'm working on the theory that restricting air flow balances the box ( pressurises ), thus distributes air evenly around the box yes, also a round box might be a nice addition to a somewhat square world !

Also on Hot air or cold air paths exit from diffuser I've balanced the size and placement or outlets in diffuser body, understanding that cold air falls hot air rises l can then blow not just across the ceiling like most other diffuser of this kind do but I can force the air to blow across also down but not directly down more on a 45 deg, what you think about that ?

One thing I've had a hard time establishing is an average supply air volume for a 595 x 595 mm four way T bar style diffuser, I'm working on a theory of 350 lts sec ( average ), what's your thoughts on this volume guys ?

To add, noise factor maybe a problem so I've also taken that into account, as we know more volume is just that more volume ( noise )

Cheers guys any input would be super great, have a good weekend, Wayne.

[Tesla]

deluxairhead
I think you need to a little more open minded and think outside the square. One of the areas that had been overlooked in the past to load match and save energy is to vary the static pressure in the system according to load or predicted load. So I think there should be two average volume flow rates, one for perimeter and one for center zone. Noise is also attributed to turbulence not just volume.

[deluxairhead]

Hi Tesla

I hear you loud and clear pardon the pun, in my understanding not everyone sets up their job the same ie : perimeter - centre zones, l had a conversation with an engineer quite some years back about this very subject it makes perfect sense and I've applied when and where i could since.
But that being said i still would like to know an average supply air volume for a standard 4 way, hope your could help here or maybe a balancing guru might like to add some words that would get straight to the point I guess yes !!

Cheers Wayne