magnetic stirrer

|> |> So I think my problem will be holding the rotor steady when it cannot |> come |> |> into contact with the pipe wall while rotating. |> |>

|> | Maybe shaping the rotor so that a layer of fluid keeps the rotor from |> | touching the sides, like the heads on a hard drive? |>

|> Something like that might work. |>

|> -- |> |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) | | --------------- | Why not a simple frame to hold the axle centered. It need not be any more | than a few "spokes" which will have minimal interference with the flow.

If the frame is part of the whole mechanism, and not affixed to the inner wall of the pipe, maybe that can be done.

| Note that anything that depends on the fluid flow or layers will not keep | the rotor free from the pipe on starting (unless you repeal the law of | gravity) so after a few starts, bits of the impellor will be floating | downstream.

At startup it won't matter (much). At full speed I want it not contacting the wall. But even at stop when it is contacting the wall, it cannot be affixed to it. It has to be able to slide out and leave the wall intact.

Reply to
phil-news-nospam
Loading thread data ...

------------- If it is free to slide, then it will. The result will be that the rotor slides "upstream" rather than pumping fluid "downstream" This is not desirable as not only will pumping efficiency drop but the rotor might move out of the driving field. You have to somehow anchor the rotor in the pipe and transfer reaction forces to the pipe. --

Don Kelly snipped-for-privacy@shawcross.ca remove the X to answer

Reply to
Don Kelly

Unless a solenoid effect will keep the rotor in the field? All unclear.. Eric

Reply to
Eric

--------------------- There is a solenoid effect (as in a conventional motor) but remember that the full pumping force equals the reaction force and this, I expect, will far exceed any expected solenoidal forces involved. Possibly a design could increase the solenoidal force but there are easier alternatives. --

Don Kelly snipped-for-privacy@shawcross.ca remove the X to answer

----------------------------

Reply to
Don Kelly

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.