[Bldg-sim] Negative pressure for EQ cr 5

[Deepa]

Thanks Cheney !


On Wed, Oct 6, 2010 at 1:43 PM, Cheney <chenyu73 at gmail.com> wrote:

> Hi Deepa,
>
> My two cents.
>
> For your question, you need to know:
>
> 1. the air volume in room and its pressure
>
> 2. To achieve 5Pa, how much more air should be introduced -
>
> Higher pressure x air volume in room/atmospheric pressure
>
> Now you get the number for the  static condition... ;)
>
> to maintain the pressure in a leaky room you have to pump in more air,
> right?
>
> 3. from the ASHRAE Handbook of Fundamentals:
>
> Q = 2610 x A x (DP)1/2
>
> • Q is the room leakage flow rate in cfm,
> • 2610 is a conversion factor,
> • A is the net open crack area of the room (generally not measurable), and
> • DP is the differential pressure.
> 4. If you'd like to maintain certain pressure in the room, you need to
> supply 2+3 first. When the pressure is established in dynamic condition,
> you need to supply only 3 to maintain the pressure you want.
>
> This is only the theoretical calculation for your reference.
> Cheers,
> Cheney
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20101006/0076dd38/attachment-0002.htm>