|> | The motor and its single coil is well below the hot zone in this design. |> | What you describe could work but would be much more problematic keeping |> the |> | coils cool. And, you would need several coils to create the phase |> difference |> | to cause rotation. Even though it wouldn't have rotating mechanical |> parts it |> | would likely be more complex. |> | |> | Small shaded pole motors are very cheap and readily available. They're |> used |> | in fans, can openers and a thousand other devices needing little power |> or |> | torque at a low price. It would be hard to design a non mechanical |> | replacement and probably not worth the effort. Don't forget the KISS |> | principle. |>
|> The idea I have for this involves a "rotor" inside a pipe, instead of a |> beaker. |> It would be for applying some pumping pressure instead of stirring. So |> the |> stator would wrap around the pipe instead of being on one end. No heating |> would be involved. |>
|> One thing I'd like to do is make sure the "rotor" does not rub against the |> inside wall of the pipe while rotating. I don't know if this can be done |> magnetically, or if it would have to apply some outward force of the |> liquid |> to balance the rotor in the center. |>
|> -- |> |WARNING: Due to extreme spam, googlegroups.com is blocked. Due to |> ignorance | |> | by the abuse department, bellsouth.net is blocked. If you post |> to | |> | Usenet from these places, find another Usenet provider ASAP. |> | |> | Phil Howard KA9WGN (email for humans: first name in lower case at |> ipal.net) | | ------------------ | | Rotors/axial pumps (i.e. propeller blades) inside pipes with polyphase | stators outside have been used for many years where it is important not to | break the integrity of the pipe- pumps for liquid sodium come to mind as an | example(the pipe in the region has to be non conductive). The rotor /pump | would have a frame and bearings to hold it in the center of the pipe.
I'm looking at doing this without any frame/bearing inside. So I need to find some means to keep the rotor steady inside the pipe. It needs to stay away from the inside wall of the pipe, as well as avoid moving along the pipe.
| As for stirrers, you can have a stirrer for conductive fluids- simply get a | stator from a polyphase motor and put it around the vessel (a single phase | stator with a resistance or capacitance supplying the start winding could do | the job. A case where this was applied was in a high power CO2 laser where | there was a plasma discharge which had to be kept uniform and not form "hot | spots". For non conductive fluids, put some sort of wobbly gizmo in the | fluid. Some sort of spindle to hold it is sufficient ( A beer can simply | dropped on the end of a paper holder spike in a rotating field will rotate | well without trying to fly off to one side - drink the beer first as you | want to use the opening where the pull tab is).
So I think my problem will be holding the rotor steady when it cannot come into contact with the pipe wall while rotating.