Paul and group,

In the interest of KISS principles would a Tesla turbine have enough
efficiency (torque) to make it worthwhile?? 

Dan

Hi Dan,

I stumbled to this Tesla turbine a year ago, first impression was it's
very simple and compact. But there's downsides:

- Very tight tolerances required, on white-hot exhaust temps.
- Low demonstrated efficiency (~45%)

( http://en.wikipedia.org/wiki/Tesla_turbine )

Tesla himself claimed that 90% will be reached with steam, but that has
not been verified with hardware.

It could be easier to make an educated guess of development potential if
 theoretical background could be found somewhere. Maybe there's thesis
work somewhere, i didn't dig very deep on this.

Personally, i would spend my imaginary million to radial flow disc
turbine with multiple, discreetly geared expansion stages collecting to
one axle. That could be very efficient. Stator could be single casting
and air cooling is easily arranged. Multiple, concentric rotors are more
tricky, but by no means _too_ difficult.

Cheers,

Petri


Here is another type of turbine that people might find interesting.

 Paul Lamar

Yes, that's the design i had in mind. Found the paper on NASA server:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19800008223_1980008223.pdf

Looking that, it seems excessive to raise efficiency from 90% to 95% by
adding the complexity of multiple, geared rotors. 90% is fair enough.

If VGT turbo turbine efficiency is somewhere 80-82% on wide power band
due to adjustable vanes, why not start experimenting with eg.
Borg-Warner units... they claim that their turbines can withstand 1050 C
[1922 F] EGT's - how long, wasn't stated ;)

http://www.borgwarner.com/

Proto system could be done with existing hardware... almost, since
matching friction drive should be made on spec, likely.
http://www.rotrex.com/

Cheers,

Petri



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