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This diagram shows the Block
VaporPressureCalculation
with a supporting ConstraintBlock VaporPressureCalculationConstraint
:The Constraint equation is:
{pressure=vapor*(gasConst*((roomTemp+celciusOff)/(molecularW*volume)))}
If you compare that with the famous P⋅V = n⋅R⋅T
ideal gas law, where n is the number of moles and R = 8.314 J/(K⋅mol)
you get:
pressure*volume=(vapor/molecularW)*gasConst*(roomTemp+celciusOff)
This implies vapor/molecularW
is just equivalent to the number of moles n
. But this makes no sense if "vapor" is elsewhere a rate mL/s, it only makes sense if "vapor" is a mass (in g).
Aha, maybe they've used a sneaky not-quite-accurate trick in the spec equation:
As it happens, 1 mL of water at most temperatures and pressures does not have a mass of exactly 1g. But even if the "vapor" were taken as g/s then the dimensional analysis suggests there is a major problem, you'd end up with the output being a pressure rate:
Also:
If you assume the
volume
is litres (L) the dimensional analysis is off by a factor of 1000.
So it seems this assumption used in this trail is correct:
And we are indeed dealing with a commercial humidifier for a large building, not a "humidified room":
Notes
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