Constructing a Fluidyne Engine: Questions & Answers

[arehman1289]

Can anyone help me in constructing a basic fluidyne engine to pump water. is the dimensioning of the tubes etc critical. any link/person can help me regarding this ??

 

[Isarmann]

Sure thing!

There is an excellent report prepared by Oak Ridge National Laboratory available which covers all the dynamics of using fluidyne engines to pump water for irrigation. Yes, the demensioning of the tubes is one of the main variables in determining engine performance, but happily, the dynamic continues to work across a broad range of possible values. So in other words, even if you just threw something together, it probably will work; but the equations involved scale well and are relatively easy to work with...

ORNLITM-10475 is the paper's official number. Let me see if I can find you a link.

And here it is: www.ornl.gov/~webworks/cppr/y2001/rpt/27113.pdf[/URL]

I think you'll find it's as complete a reference as you'll need to do all your calculations. If you have any trouble, ask about it and I'm sure we can hammer out the actual dimensions you'll want to use.

Hope it helps.

 

[arehman1289]

very nice link mate. very informative. i hope u will help me if i have any problems while constructing it.
thank u

 

[Isarmann]

Certianly. I'm glad it fills the bill. Let me know if you want to discuss any particulars...

Incidentally, there's someone who's been posting YouTube videos of small example fluidynes running... It's a little odd, because while the engines are very nicely made, and the videos well-produced, he doesn't seem to be showing any actual use-- it's just the engine running. The reason I am bringing the video to your attention is that they give a very good impression of the frequency the engines oscillate at, and what that looks like.

All the best for your build effort!

 

[arehman1289]

yes i viewed some of those videos.
i plan to operate a pump using this engine but at the moment i am constructing a small prototype version. it is running but not that smoothly as expected.
i wanted to ask about the allowable variation in the diameter and lengths of the tubes used ??

 

[arehman1289]

hey there
can anyone give me research paper or tell me the mathematical equations that govern a fluidyne pump.
specifically if i want a required power output how to calculate
1) the heat input required
2) the dimensioning required of the displacer and tuning columns
3) predict the motion of the oscillating columns

any hepl pleasez ??