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Unread 29-01-2015, 10:25
jee7s jee7s is offline
Texan FIRSTer, ex-frc2789, ex-frc41
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Re: Help Calculating time to recharge air tanks

Quote:
Originally Posted by nuclearnerd View Post
1) Assuming temperature stays constant (not a fair assumption maybe):

P1 * V1 = P2 * V1 (from the ideal gas law)
This is a bad assumption. The ideal gas law assumes that the energy in the system in constant. The compressor of course puts energy into the system, so that violates PV=PV.

Patrick has the curve for you. It's a calculus problem as he says: Take the integral of the time to fill each step based on the spec.

I'm still a fan of the aforementioned stopwatch method. Or, go to Viair's page, look at the 0.5 gallon fill rates and divide by about 3.3 (0.5 gallon = 115.5 cu in).
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