Re: [TeslaTurbine] Re: TT disk material
- Tom, Smooth helps the boundary layer stick. Rough will cause laminar flow
and disturb the adhesive aspect of the boundary layer. Telsa mentioned this
in one of his many papers, I think it was in " Tesla's Engine A new
Dimension for Power. complied by Jeffery A Hayes available at TEBA.
- --- In TeslaTurbine "Kent L. Aldershof" wrote:
>is that the SS
> <snip> > I think the advantage of using SS instead of cold-rolled
> can be polished to a smoother and brighter surface finish. Thisimproves
> the adhesion, and should add to the efficiency of your turbine.I
> The issue is not tensile strength, but surface finish. If you use
> unpolished SS, you would not be much better off than by using CRS.
> think tests of identical runners, one of polished SS and the otherof
> plain CRS, would show that the SS runner would perform significantlysupply of
> Sorry if this is discouraging, if you aren't able to get a free
> SS to match your free CRS.The turbine would have to be designed around the available diameters,
but disks could be scavenged from old computer disk drives. They are
polished and flat to microinch tolerances, and designed to be spun at
high speed. I'm still finding discarded 5-1/4 inch drives, and 8 inch
disks should still be obtainable.
- --- In TeslaTurbine@y..., "wyzed" <wyzed@f...> wrote:
> Tom, Smooth helps the boundary layer stick. Rough will causelaminar flow
> and disturb the adhesive aspect of the boundary layer. Telsamentioned this
> in one of his many papers, I think it was in " Tesla's Engine Anew
> Dimension for Power. complied by Jeffery A Hayes available at TEBA.Tesla was a genius and so he may be correct, however:
1) a rough surface should cause turbulent and not laminar or smooth
2) Since the goal of a turbine is to essentially cause "friction"
between the surface and the working fluid or gas, one could also
argue that the more roughness the better.
3) On page 68 of "Performance of Multiple-disk-rotors Pumps with
Varied Interdisk Spacings", by Joseph H. Morris, "Significant
increases in pressure rise were noted fo the roughened as compared to
smooth disks." Also "Improved pumping performance was noted with the
roughened disks as shown in Tables..."