ecological turbine Archimedes screw

[izentrop]

The screws of Archimedes, it's like in love, the longer it is ...
Still a diy turbine (I guess).
160 W supplied with 20l / s on a drop of one meter ... efficiency> 80%?
https://youtu.be/Ntbgu4SEShw

[Christophe]

it's like in love, the longer it is ...

Long temporally yes ... long in length, not completely agree, need some width

By the way we say big and not long

Nice micro screw, that's what I should put in my creek!

Technical level is how much thread to screw? I saw 4 on another video that you posted. Is there a rule in this sense?

[Forhorse]

I would say that the better there is.
As for screw reducers (screws / crown) if the screw has only one net, the reducer is not or practically not reversible (the screw can cause the crown but if we try to cause the crown it locks : for a lot of application it's an advantage)
But if the screw begins to have 3, 4, etc ... nets the reducer becomes reversible: the crown can cause the screw.
There must also be a correlation with the pitch of the screw, a fine step will be much harder to train than a very wide step (and a larger number of nets necessarily implies a step greater than with a single net)

[izentrop]

To set the screw http://rugc15.sciencesconf.org/55086/document

[Christophe]

I would say that the better there is.

Okay ... unless we talk about mass
Finally, we need something for everyone!

End of parenthesis

Thanks izentrop for the document!

24, boulevard de la Victoire 67084, Strasbourg, INSA Strasbourg

Here I know that me !! It was "my" fluid mecha lab!

[chatelot16]

we can not fill the table to give a yield to each type of turbine!

each type of turbine has a variable yield according to the conditions of use and according to the quality of realization

some turbine have a good performance at a nominal flow and pressure, and become lamentable as soon as one deviates ... others are more versatile

: a versatility of a wheel or turbine depand of its management ... the screw of archimede or the wheel wise are similar: how to do when one wants to reduce the power ... one can reduce the speed of rotation and leave the wheel or the screw full of water ... it's quite complicated, it requires a large electronic dimmer ... we can also keep a constant speed and reduce the filling of the screw or wheel ... it's a bit of loss of energy at the valve that is filling, but it can be optimized if the valve has a shape adjusted to the wheel or the screw

the main problem and that the valve which controls the filling has a rather slow effect on the power: when one opens the power does not increase instantly, it is necessary to wait until it turns so that it fills up

the francis turbine is practical for the autonomous electric generator because it has a very short response time: when one new power increases instantly: a good regulator can thus make a 50 Hz as precise as a diesel

the peleton is also practical for speed regulation! it is widely used for the high drop of EDF, and the more it builds small plus usable pressure range shifts down ... it does not surprise me at all to see mini peleton

[lilian07]

This type of screw is really similar to the type of wheel called from below as the Sagebien with its big yield on a reduced spectrum of flow / slope because the main problem is its low speed of rotation which prevents it from to be reactive (but that's not too serious in itself) and prevents it from getting out of its operating range or its performance dropping dramatically.

It must still work relatively well for our small streams and the more it is useful to pass the fish.

Another problem that I see there, you have to master quite the height of water and it is the geometric design of the building that must ensure that (a little complex) and our small streams are capricious and flows really variable (especially in the south and since climate change).
Finally I think that the screw is rather complex to achieve in self-construction, I prefer the small Pelton when the altitude approaches the 10m (infrastructure much less imposing and less complex) ... below 8m of uneven why not (see the final confrontation with its price but I hope it is not that expensive ...).

[izentrop]

Hello,

Technical level is how much thread to screw? I saw 4 on another video that you posted. Is there a rule in this sense?

A fortnight in the last video, a luxury maybe

It gets 84% mechanical yield with 3 fillets and with a good flow rate range around 80%.

More turns:

• Increases the nominal flow
• must yield, with a maximum around 4 or 5 turns
• must allow to gain operating range in terms of flow while keeping a maximum yield.

The interest of the Archimedean screw is to keep a maximum efficiency over a wide range of flow, without mechanical complication, while maintaining a sufficient step to be ichtyocompatible.

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[chatelot16]

the more you increase the number of netting, the more the water will have to cross a large number of times the leakage of the screw adjustment, so the lower the loss of energy per leak will be

do not excessively increase the number of threads as you will increase the friction of the water on the screw

for the reversibility of a worm is not the number of net that counts but the angle ... and of course when you want a large helix angle it takes several net

with the water archimede screw a low helix angle does not reduce much the yield as the friction of the water is low

how to do with a variable water height? for the downstream height it fits all alone: ​​if the downstream level increases the lower part of the screw will be completely drowned and will not do a great loss of energy if the speed is low enough ... it is less serious that the wheels below type culelet that works at the speed of the water jet and loses all its effectiveness if the bottom of the wheel is not out of the water

the upstream level variation is low when running over water: it is simply the maximum level of the dam

if you want to store in a body of water you must vary the flow ... the classic solution of the wheel wise, it is a valve that serves as the upper part of the courier: the water enters the wheel in passing over the valve: it is therefore possible to choose the height of entry into the wheel and to adapt without loss to the upstream height

[oli 80]

Hello, here is an old subject that I found or this archimedean screw was evoked energies-renewable / hydroelectric turbines-t9043-10.html

cordially