Temp fluctuation affect?

[Fred Sturm]

Even in a sealed system, I believe water would migrate from wood to air
with a rise in temperature (and corresponding lowering of rh). And would
migrate back to wood with a lowering of temp (and corresponding rising
of rh). The amount of moisture in the sealed system would remain
constant. It would just move from atmospheric (gaseous) to liquid and
vice versa. 
	The fact that wood is involved adds the factor of its "hygroscopic
attraction" (or whatever that should be called), but to make it more
simple, suppose you just have a dish of water in an enclosed space. As
temperature increases, less water will be in the dish, and more in the
air. And vice versa. I expect it's largely a matter of energy being
available, and the water molecules taking advantage of its presence to
become gaseous (not a scientific way to put it, but kinda sorta what
happens).
	Or am I missing something?
Free Sturm
University of New Mexico
Ray T. Bentley wrote:
> 
> Sorry, guys.
> 
> I've taught science too many years to accept that the relative humidity
> change has anything to do with the change in wood moisture content.
> Relative humidity changes as temperature changes, but the actual amount of
> moisture may indeed stay the same.  I understand all about dew point, etc.,
> but actual moisture content does not change because the relative humidity
> does UNLESS the temperature stays the same.
> 
> A sealed container of air (or wood)may hold X amount of moisture.  If it is
> heated, its relative humidity goes down, because it is capable of holding
> more moisture at a higher temperature.  The converse is true upon cooling.
> True, wood being a solid, there is less difference caused by temperature
> than in air.  But the content doesn't necessarily change with the relative
> humidity reading which depends upon the temperature at which the humidity
> reading is taken.
> 
> Ray T. Bentley, RPT
> Alton, IL
>