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Unread 29-01-2015, 10:42
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JamesCH95 JamesCH95 is offline
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Re: Help Calculating time to recharge air tanks

Quote:
Originally Posted by pfreivald View Post
Okay, I think I've got it. Integrate the curve between the pressures whose charge time you want, set that equal to the difference in energy of the gas (delta-P*V) over time, and solve for time.

Yes?

(Man, I need a nap.)
This is what I would do. Even this is slightly optimistic as the air will cool off as it flows into, and sits in, the storage tanks. Accurately modeling the compressors performance will be a bit more than trivial.

A decent sanity check would be to take the compressors electrical power input, multiply by a conservative assumption of efficiency, and divide the difference in stored energy by this power to get time.

OP - your initial approach makes too many optimistic assumptions such as no temperature change, constant flow rate vs pressure, etc.
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