Lloyd quoted an article thusly:

> "This difference of temperature encourages a movement of
> convection that drives the moisture produced by the bees
> into the gaps that separate the follower boards from the
> sides of hive and away from the cluster. Most of the
> water vapor condenses against the sides of the hives and
> does not shower the hives."

> The author is maintaining that warm moist air does not rise
> but somehow is 'driven' toward the sides of the hive next to
> the follower boards.  Why the sides of the hive, and not the ends
> (which are not adjacent to anything similar to a follower board)
> is not discussed. Is there any possibility he is correct?

First, I can't see any "passive closed convective loop" air circulation
in a beehive having enough speed/volume to prevent condensation under
most possible conditions in a beehive.

Second, I can't see the increased empty space between the hive body and
the follower boards improving the speed/volume of convective airflow to
prevent "inner cover condensation" under most conditions all by itself.

Jerry said:

> Robert Madsen, Dull Knife College has been looking at air movements
> inside hives with a temperature probe positioned every 1 inch of space
> in all dimensions.

This is very interesting.

How does he successfully measure airflow with temperature probes?
If temperature is being measured, is airflow is being extrapolated
with a (very fancy) model that makes assumptions about temperature
deltas implying a direction to air movement?

Lots of folks (me included) have thermocouples in a few hives.
If his data is anything like mine, he should have a consistent and
sharp drop-off in temperature a very short distance from the cluster
edge.

Doesn't the sharp drop-off in temperature at the cluster edge indicate
a LACK of airflow around the cluster?  If there is a serious convective
loop going on, wouldn't we see more gradual temperature drops as one
moved away from the cluster's outer edge on at least the "sunny side"
of the hive?  (Note that the "sunny side" for my hives is never the side
where one might put a follower board - I point my hive entrances south.)

Taking the opposite view just to make a point, if I create a model that
extrapolates airflow from temperature changes, does my cluster edge
temperature data imply that I have a very scary and massive flow of
air around the cluster, constantly removing heat from the outer
surface of the cluster via "wind chill"?  Clearly not, but how do I
know that any one pair of temperature deltas indicates airflow between
the two points?

> Its basically hotter air rising and cooler air dropping, moving around
> the perimeter of the frames.

What sort of airspeed and flow volume are they extrapolating? Enough
to keep condensation from happening on the inner cover if you put in
follower boards?  :)

...and the bees don't matter?  This would imply that the moisture
generated by the bees has NO EFFECT AT ALL on air movements within
the hive, and everything is temperature-driven.  I agree that moisture
content itself has little impact on the buoyancy of air even under the
best of conditions, but the surprise is that there is enough air exchange
between the hive and the outside world to make the bees' waste heat a
non-issue, but not enough to disrupt the convention loop.

What sort of "leakage" does he have on these hives?  Did he seal them
tight for the testing, or does he have a "typical hive" configuration?

                        jim

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