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how to make a solar-heated artificial tornado?
29 sep 1996
some people who want to make inexpensive solar thermal electricity are
becoming intrigued by tornados. high speed winds are generated in these
naturally occuring phenomena...
the franklin institute in phila used to have a heat-activated organ pipe.
they also had a tornado simulator: a small electric heater (50 watts?) at
the bottom of a glass tube about a foot in diameter and 6 or 8 feet tall.
when a visitor pushed a button on this exhibit, the heater turned on and
some smoke filled the tube, and the smoke started swirling. it's better to
have a swirling updraft than a straight updraft, if we are trying to make
electricity with a turbine, no?
from the mcgraw-hill encyclopedia of science and technology...
some excerpts from tornados, in vol 18...
a violently rotating, tall, narrow column of air [hey, valerie, a vortex!]
typically about 100 m in dia, that extends to the ground from a cumulonimbus
cloud.
many tornadoes evolve as follows: the tornado begins outside the
precipitation region as a dust whirl on the ground and a short funnel
pendant from a wall cloud on the southwest side of the thunderstorm.
it intensifies as the funnel lengthens downward, and attains its greatest
power as the funnel reaches its greatest width and is almost vertical.
so the most powerful part is not at the narrowest point, near the ground?
then it shrinks and becomes more tilted and finally becomes contorted
and ropelike as it decays.
chaos, vs. what appears to be orderly physics, in life:
the central pressure deficit can be estimated by assuming that the flow,
to a crude approx, is a rankine's combined vortex, that is vertical and
radial velocities are zero and the tangential velocity is v=v_m*r_c/r
for r>r_c and v=v_m *r /r_c for r
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