Air Curtain Infiltration for Warehouse

[eljuan]

Hi, has anyone seen hard data on infiltration through an industrial air curtain?

I'm looking at heated Wing and Berner models in the range of 500k-700k BTU/hr for large roll-up doors. My application is a warehouse where there is a 12' x 12' rollup on the west side and two 10' x 10' truck bays on the east side that will be open all the time. Customer specified that doors will remain open; can't close them due to too much traffic. We're figuring prevailing W-E winds of 15 mph. We are also heating the space with unit heaters in the same HWS loop. The building is a metal pre-engineered type structure with insulation.

Now that I've described my room, here's the questions:

What type of infiltration (due to doors only) can I expect with this scenario?

ASHRAE mentions 60%-80% efficiency for air doors. Is there a better way of calculating my Qinf than using 30% of the wind volume at outside temperature?

-Thanks-

 

[ChasBean1]

eljuan,

Here's what you need to do.

1. Find out how much air mechanically comes into the whole building (via minum outside air at AHUs, make-up AH or HV units, etc).

2. Find out how much air leaves the building (via un-returned exhaust, all systems, including toilets, task exhaust, etc.).

3. Hire an air balancer to very accurately determine 1 and 2 during normal building operation.

3. Scope out that the balancer must make 1 higher than 2 by at least 10%. This may involve fan sheave adjustment.

Then, the answers to your questions are:

1. None, assuming no-wind conditions, and

2. Yes, you just did it. There will be very little or no infiltration under normal conditions, and minimal under windy conditions.

Regards,
CB