How to calculate server room air flow requirements
The basic formula for translating is:
BTU/hr
CFM = -------
1.1 * delta-T
Delta-T is the temperature differential between the two sides of the barrier in Celsius. The 1.1 value is a fudge factor for the air's heat-carrying capacity, which we can't figure without percent-humidity. Since we don't know the temperature of the room being cooled, here are some values based on 5K BTU/hr and a 72 degree intake.
Room T | CFM
----------------
| 74 | 4132 |
| 75 | 3030 |
| 76 | 2066 |
| 77 | 1623 |
| 78 | 1420 |
| 79 | 1165 |
| 80 | 1033 |
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For comparison a certain portable AC unit I just looked at is rated for 10,000 BTU/Hr and runs at about 220 CFM. It can get such low flow rates because for that unit delta-T is a lot higher than what you're attempting here.
I understand why that is an undesirable option though. Those need drains, or a scheduled bucket-brigade, as well as routine maintenance to keep running.