steam turbine and generator

 Hmm, had to misuse the internet again....

If my calculator and old brain are not completely off, the stated distance above is around 100 atom diameters (of the larger kinds, but his turbine was not built from hydrogen I think).

Quite impressive with a bit of bluetak. Unfortunately we can't ask Mr. Chaddock how he measured it.

I formally apologize If I should be wrong...

Greetings, Hansrudolf

Keith I sort of knew about Prof Chaddock’s work. I had a long chat at MEX when it was at Wembley. This lead to a long correspondence between, us mainly about nozzles. I had an idea that the low output could have been due to shockwaves developing in the throats of the nozzles.

In the end (with some help from some Hitile designers –well the Rapier missiles did not often miss). After lots of calculations on my PC I found the steam flow was almost certainly sub sonic.  So it was ‘Hay Ho’ and back to the drawing board.

Paul are you talking about ‘pea bulbs’ –which do not care if it is AC or DC-.   

Hansrudolph sorry I missed your posting

How it was done (I used the same technique). You spun the rotor on a pair of knife edged (mine were Razor blades). You found the heavy side and put a smear of blutak on the opposite side of the wheel to make it heavy (er).  With a scalpel scrape some off the heavy side of the rotor.  If the blutak was heavy then you scrape a little of the blutak.  You spin the rotor after each process. Every now and again you scrub the rotor clean,dry it and start again. Repeat the process as required until the rotor’s stopping point is truly random.  Prof Chaddock, who was far more skilled than I, claimed to be able to get centre of rotation of his rotors within 0.000002” of the true centre of balance of the rotor. I got mine so there was no detectable vibration at 5000 rpm when spun with air. The guys where I worked were very helpful –they made gyros- and helped with the vibration tests.

Hi

I made this small turbine some years ago. With 25psi it will produce 10000 rpm.

I had a hell of a job trying to balance it enough so I did not have to screw it to the bench.

The turbine it's self is 1.3/4” in diameter and has 8 blades.

It was made as an experiment to drive a locomotive throw a gear box which it did quite well but the gear box was far to big as I needed to get 10000 rpm down to 60 rpm.

I have just tried it driving a small DC motor that I got from the local model shop for £6.50. it has an out put of 12v @ 3 amps @ 1000 rpm.

I connected then together with a bit of plastic tube and put my meter across the out put of the motor and apart from the noise it went well and lit a car head lamp bulb until the plastic tube broke. I will pick the bits of the tub out of the roof later.

James.

Paul,
somehow the forum mail does not seem to work wit me! So I try
a direct mail:


I'm the Swiss gentlemen who wrote the ME articles. This is the first
time I participate in this forum. I thought to have sent of a reply to your
problem about half an hour ago - but it does not show on the forum. So I try again.


My
turbines are the size you are looking for. They are described in ME 4281,
September 2006 (Tesla, mechanical) and ME 4318 and 4320, February 2008
Laval,turbine-electric). Try to get hold of these issues. For any futher questions please contact me directly.


A further contibution about my latest locomotive with turbine.electric
drive lies with ME since last June. They have not gotten around to publish it
yet.


Key to success is to keep electrical and mechanical losses of the
TG-unit as low as possible!


Werner
Jeggli/Switzerland
 

Edited By Katy Purvis on 01/06/2015 11:25:39

Mtroniks Vision 500 Marine >>

Hi Paul,

if you need a motor which will not disintegrate at turbine speeds, look at the so-called inrunners as used by the aeromodellers.

See e.g. this site:

http://www.jethobby.com.sg/cgi-bin/ezsite/index.cgi

select 'brushless motor',  then 'GS inrunner'

The first I see, B-12-30 (12 mm dia, 30 mm length will turn over 45000 rpm on 12 v, and pulls 3 amps.

And there are others, even faster.

Even if it possibly is somewhat less as generator...impressive.

I admit that I have absolutely no experience with these or wit any similar motors. But that's what I would look for.

Greetings, Hansrudolf

Edited By Versaboss on 16/01/2011 23:23:50

Paul, no they are in Singapore, and the prices are Singapore dollars  (100 SGD = 49 GBP according to my converter). But it seems they don't have an online shop; I was a bit mislead here myself.

Edit: or maybe they have? I see now a 'add to cart' on some items!

Surely you can find a shop catering for aeromodellers, or try Ebay.

As I said I have no experience with these motors, but as they are principally ordinary DC motors (but with the windings outside and a magnet rotor in the case of an inrunner) I see no reason why they would not work as generators.

Edit 2: maybe the 3 leads would need to be connected to the usual 2 (+ / -) with diode bridges, if my theory of their working is correct.

I remember that quite a time back someone wrote an article in MEW about building an outrunner (where the windings are inside and the case with the magnets turn) for driving a milling spindle. These are not so fast, but have more torque.

I'm sure someone will bring forth the number of that issue.

Greetings, Hansrudolf

Edited By Versaboss on 17/01/2011 23:49:44

Edited By Versaboss on 17/01/2011 23:58:52