I have been thinking for some time now about the UQ and winter camping issues.
Insulators such as down vs. air-mattresses.
And how they compare.
About heat loss, and heat retention, and such like things.
I have read about radiation vs. convection . . . and try to wrap my mind around it all.
I tend to . . . in my limited way . . . think microscopic . . .
What follows are some of my thoughts . . . all be it, not so scientific; yet more layman:
The bodies feeling of cold or warmth is a function of: artificial/generated heat or bodily/internally generated heat.
When in a hammock we rely on the latter,
and how cold or warm we feel is basically dependent on
heat retention, or a lessoning of heat loss.
In relation to this or a way I understand heat exchange is like the oceans or air,
And being that air is the understood/agreed insulator
it could/would be advantageous to understand how it all works.
First the oceans are heated by the sun
and are hottest at the suns apex on the earth
and coldest at the poles.
Heat causes currents, and the result is ocean currents.
The concept is basically the same with air.
OK . . . next I want to think of the down/thinsulite UQ or pad/air-mattress
If it is the air inside that is the actual insulator why is one system better that the next.
I think it is how the system traps the air and what it does with or to the air that makes the difference.
First Going back to the thought that the human body is the heat generator,
And it is the free outside ambient air that is the heat robber,
By wicking the heat away so to speak,
We need something between the two, to lessen the heat wick action.
Air . . .
By capturing the air in an air mattress (AM) we create a barrier between the free air and our body.
Our body generates the heat and raises the temp in the AM
Inside the AM there is a closed system of air that is much like the oceans,
Where as, the heat next to our body is setting up currents in that system.
The out side free air, which there is so much more of,
is wicking away heat from the distal side (far side/outside)
of the AM cooling that portion of trapped air.
This sets up currents or even a direct heat-loss flow in the AM,
From the proximal to the distal parts of the AM,
And with no resistance within the AM’s structure,
The flow is quite rapid . . . convection.
Slow down the rate of flow of the heated air from the proximal
to the cool/distal area of the system.
Enter, goose down, thinsulite, Climashield, or any other, such as quilt batting.
The solids in the enclosed area slow the movement of air from proximal (close to you) to the distal (far from you).
Some actually trap the air in segmented areas so that airflow is restricted, maximally.
Now the transfer of heat is more in the way of radiant heat loss.
The transfer of heat from solid to solid . . . so to speak.
This is a much slower process.
So as you lay there in your hammock your body is producing heat . . . infinitum.
Or at least while you’re alive.
Your body heat warms the fabric next to you and the conveyance of heat starts.
The more partials and the type of material used,
in the enclosed area, to slow air movement,
To, retain heat,
is all what matters in staying warm.
Some stuffing’s are just better than others at doing the job.
I think the take home here is Air mattresses are for comfort,
Not insulating . . .
And blue pads are a good barrier, but have little air . . .
Little air = little insulating value.
Kinda like sleeping on a 2x4 as far as R-value goes.
Just me thinking, I hope that helps
and sorry if some of my words might not seam to work.
O . . . O
Now I need to commit to submit