Nested rotations in a fluid: Implications and Visualization

AI Thread Summary
A fluid can exhibit visible rotation without having a net angular momentum due to counter-cyclical internal movements. This concept suggests that fluids can contain multiple scales of rotation influenced by thermal energy, as seen in a jar of water spun at high speeds. The discussion proposes that manipulating these rotations could lead to macroscopic angular momentum emerging from thermal energy, potentially facilitating eddy-to-mean energy transfer. This process involves converting small-scale energy into larger, usable energy levels through dynamic pressure fields. The importance of vorticity in fluid dynamics is emphasized, highlighting its role in determining flow characteristics.
kmarinas86
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A fluid visibly spinning clockwise doesn't necessarily have a net angular momentum. I figured that this might be the case by considering that the fluid rotations within might be counter-cyclical. It would appear that you could apply this relationship many-fold times, where a fluid consists of various scales, which vary according to rotation vs. counter-rotation.

Furthermore, if one could a imagine a closed jar of water at room temperature, the water itself could consist of many such rotations due to the thermal energy it contains. I wondered then what would happen if you spun the jar of water close to speed of sound in water, without breaking the jar. I imagined then that it might be possible to increase the scale difference of different levels of rotations, so that way macroscopic angular momentum might appear to emerge from a fluid, derived from the initially present thermal energy. I figured that such is perhaps a mechanism for eddy-to-mean energy transfer, which, if I understand, is actually a kind of energy conversion process, where energy already present in the very small can be pumped up to higher levels of scale which are accessible by conventional technology. This could involve, for example, the manipulation of the static pressure into a scale-variant dynamic pressure field, which is such that the curl of the field could alternate between left-handed and right-handed orientations with respect to the scale of rotation, or even more specifically, the scale of rotations considered in the model. This would be a rotational version of eddy-to-mean energy transfer.

http://books.google.com/books?id=2RiCKmdlXrUC&q="even in nearly irrotational flows the relatively small amount of vorticity present"
Clifford Truesdell said:
All real fluid motions are rotational. Even in nearly irrotational flows the relatively small amount of vorticity present may be of central importance in determining major flow characteristics, and even some of those whose interest in fluid dynamics is only of the practical sort are now beginning to learn that hitherto largely neglected question of vorticity must at last be faced.

To give you a sense of what I'm visualizing, I uploaded a picture below:

https://lh5.googleusercontent.com/ciXr2nzrVjClk0lamMp6ralLAbsoTmotbYeh_Gm8zaRfIq3GHsc3gd9vIo6rYP72JEDSt7miNPM
 
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kmarinas86 said:
To give you a sense of what I'm visualizing, I uploaded a picture below:

[PLAIN]https://lh5.googleusercontent.com/ciXr2nzrVjClk0lamMp6ralLAbsoTmotbYeh_Gm8zaRfIq3GHsc3gd9vIo6rYP72JEDSt7miNPM[/QUOTE]

Here is a more stable link to the picture:
https://docs.google.com/open?id=0B4C1RIYfRPYtOTk4dXc2ZGJjX2M
 
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