Conservation of angular momentum in coriolis generated tornado funnel

AI Thread Summary
The discussion centers on the observation of tornado funnels and Coriolis-generated water funnels in draining sinks, specifically regarding the relationship between angular velocity and radius in these systems. A participant expresses curiosity about how the increasing angular velocities of water with decreasing radii seem to contradict the law of conservation of angular momentum. They reference the formula L = mvr and suggest that if mass remains constant and velocity increases due to gravity, the radius must decrease consistently over time. This leads to a visualization of vortices, which the participant finds intriguing. Another contributor provides a link to a resource about Coriolis effects, indicating a misunderstanding of the original experimental setup, which was thought to involve a controlled environment to study vortex behavior. The conversation highlights a fascination with the dynamics of vortices and the complexities of angular momentum in fluid systems.
carl fischbach
After careful observation of tornado funnels and
coriolis generated water funnels of draining sinks
the increasing angular velocities of the water
with reduced radii is greater than allowed for
by the law of conservation of angular momentum.
Could someone shed some light on this situation
for me.
 
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I don't know, I've never heard of this, I think it is very interesting. If I remember correctly, L=mvr. And if we assume m is constant, and (the absolute value of) v is increasing due to gravity, then the derivative of the radius as a function of time should be a negative constant (indicating a constant decrease in radius). When I visualize this, it seems to correlate nicely with the picture of a vortex in my head. Please post everything you know, though actual data may be a bit much to type up. Regardless of what anyone says in this thread, I'm going to look into this, I find vorticies fascinating.
 
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Good point, I misunderstood what he was saying. I thought he had an experimental setup of a tub (w/ hole) mounted to the rim of a lazy susan type of thing, that way he could reliably get vorticies of known angular velocity, size, etc., given the angular velocity of the lazy susan thing, radius of said thing, etc..
 
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