Thank you for sharing your experiment! I just learned something (and hope it sticks). The change of flow in contact with the immersed object was much like that in contact with icebergs. Safe travels and Happy Returns!
I have presented your video experiment in a "Dynamical Oceanography" course for undergraduates of Oceanography. And also for a "Coastal Dynamics" course. Your video is awesome Jonathan. Set up, explanations, side views, and of course, music.
Nick Moore Theory: For constant density fluid, the distance from the rotation axis doesn't come into play here. So the results shouldn't differ. Experimentally: You can get large air drag on the upper surface of the fluid layer in a larger radius tank that is spinning rapidly. That can effect and/or destroy a column.
Simply put, every column of fluid acts as an axially-aligned gyroscope. If the gyrscopic effects dominate all others (e.g., viscous drag) then the fluid column above the puck cannot be displaced. This is called the Taylor-Proudman Theorem. A moderately detailed explanation can be found in "Physical Fluid Dynamics" by D.J. Tritton.
john zamer They can form over seamounts. But more importantly, when deep convection events occur in the Weddell and the Labrador Seas the fluid forms a huge Taylor Column like Chimney that then break apart into baroclinic cones, and this is how new deep ocean water is formed. Relevant for sure for planetary climate.
Apologies. It is how surface water masses, which typically stay near the ocean surface, can be fluxed down into the deep ocean. This is a crucial aspect of the deep ocean circulatory system, which in turn is relates to how the ocean transports and stores heat. Hence the relevance to climate...
@@johnzamer3142 Hmmm. If the vorticity of the rotating object was far less than the typical vorticity of the fluid, then the rotation of the object would be of secondary importance, and the columnar response would likely still be viable.
Just saw this. Very interesting. Could be an Taylor Column byproduct ---See the paper by Bloxham & Bush in Physics Today (I think). They show something similar, although in an wider container. Is that ping pong ball filled with air or does it also have some water? Also, what happens if you use a wider cup?
I'm probably wrong. As far as I can tell the flow of water over the top of the object creates a column of pressure. Not sure if it is greater pressure but that flow would create a bulge. We could see it as a cylinder or a mound of water. The ater flowing upward would fall downward away from the center of the object. Like a water fountain jet falling onto itself.
@@Moriandrizzt I don't understand what you mean when you say the jet would fall into itself, what flow are you talking about ? The only flow i can see is the rotating one due to the slight angular acceleration. Can you tell me more ? The only thing I see is that there has to be an equilibrum between centrifugal force and pressure gradient force. But I can't understand how this could end up in creating a column of water that canno't move...
Thank you for sharing your experiment! I just learned something (and hope it sticks). The change of flow in contact with the immersed object was much like that in contact with icebergs. Safe travels and Happy Returns!
Thanks for sharing. Fantastic video. Students will love it. (UFSC / Brazil).
Yeah I confirm ;-) greez from Switzerland to Brasil.
Cool. Send me feedback. How can I improve these for student consumption? (I usually dont get to teach this material in my classes...). ---Jon
I have presented your video experiment in a "Dynamical Oceanography" course for undergraduates of Oceanography. And also for a "Coastal Dynamics" course. Your video is awesome Jonathan. Set up, explanations, side views, and of course, music.
Excellent video showing the Taylor-Proudman theorem.
Very cool, does the effect get stronger or weaker the farther you are from the axis of rotation?
Nick Moore Theory: For constant density fluid, the distance from the rotation axis doesn't come into play here. So the results shouldn't differ. Experimentally: You can get large air drag on the upper surface of the fluid layer in a larger radius tank that is spinning rapidly. That can effect and/or destroy a column.
ucla spinlab Thanks, I may have to bust out the angle grinder and my high speed camera to see if rotational speed makes difference.
Do it! Love to see what your high speed camera can do here...
I'll add it to my list of "outdoor experiments."
You guys have some awesome stuff, keep it up!
Thanks. You too. In fact, we have liquid metals in the lab as well (gallium). So if you are in Los Angeles, or nearby, we should talk...
Which music is it?
Does water temperature affect how the theorem works due to water crystallization? If it doesn't, how could it happen in the Arctic sea?
just one question....what's the physics behind it..??
Simply put, every column of fluid acts as an axially-aligned gyroscope. If the gyrscopic effects dominate all others (e.g., viscous drag) then the fluid column above the puck cannot be displaced. This is called the Taylor-Proudman Theorem. A moderately detailed explanation can be found in "Physical Fluid Dynamics" by D.J. Tritton.
For a relatively simple explanation, I would suggest DJ Tritton's explanation in his text "Physical Fluid Dynamics".
Geophysicist here. Any idea where this may occur in the sub surface?
john zamer They can form over seamounts. But more importantly, when deep convection events occur in the Weddell and the Labrador Seas the fluid forms a huge Taylor Column like Chimney that then break apart into baroclinic cones, and this is how new deep ocean water is formed. Relevant for sure for planetary climate.
@@spinlabucla how does that form new water?
Apologies. It is how surface water masses, which typically stay near the ocean surface, can be fluxed down into the deep ocean. This is a crucial aspect of the deep ocean circulatory system, which in turn is relates to how the ocean transports and stores heat. Hence the relevance to climate...
@@spinlabucla the question I have is...would a Taylor column occur if the obstacle was rotating
@@johnzamer3142 Hmmm. If the vorticity of the rotating object was far less than the typical vorticity of the fluid, then the rotation of the object would be of secondary importance, and the columnar response would likely still be viable.
See: th-cam.com/video/1-X6OV4lVuQ/w-d-xo.html
Is this a Taylor Colomn mechanism?
Just saw this. Very interesting. Could be an Taylor Column byproduct ---See the paper by Bloxham & Bush in Physics Today (I think). They show something similar, although in an wider container. Is that ping pong ball filled with air or does it also have some water? Also, what happens if you use a wider cup?
choice!
nice vid.... shame about the music....
so... If anyone has an intuitive way to understand what's happening, I beg you to shaire knowledge, cause now I'm completly lost
I'm probably wrong. As far as I can tell the flow of water over the top of the object creates a column of pressure. Not sure if it is greater pressure but that flow would create a bulge. We could see it as a cylinder or a mound of water. The ater flowing upward would fall downward away from the center of the object. Like a water fountain jet falling onto itself.
@@Moriandrizzt I don't understand what you mean when you say the jet would fall into itself, what flow are you talking about ? The only flow i can see is the rotating one due to the slight angular acceleration. Can you tell me more ?
The only thing I see is that there has to be an equilibrum between centrifugal force and pressure gradient force. But I can't understand how this could end up in creating a column of water that canno't move...