new concept of Stirling engine

Discussion on Stirling or "hot air" engines (all types)
Bumpkin
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Re: new concept of Stirling engine

Post by Bumpkin »

Hi normandajc. I too can't see the operating principle from the diagrams. I'm guessing you're principle is similar to the Ericsson engine https://en.wikipedia.org/wiki/Ericsson_cycle but different enough to be patentable? That engine worked and addressed the dead space issue of large exchangers/regenerators, but it's noteworthy to me that he later went back to Stirling engine variants. Perhaps the extra mechanism was too much trade-off, but if you can enhance the positives and minimize the negatives who knows? Good luck with your work.

Bumpkin
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

Dear Bumpkin
Thank you
To direct the gas into one pipe or another, I was thinking of something simple see figure https://secure.digiposte.fr/p/f5d746fce ... 7793daac38
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

I forgot to say thank you to Sadi and Tom Booth
Tom Booth
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Re: new concept of Stirling engine

Post by Tom Booth »

I've been studying your design for several days now, off and on as time permits.

I've changed my mind regarding your heat exchangers. It appears from your arrangement that the flow in both directions will be effectively continuous rather than intermittent or cyclic. I see no reason why that should not work very effectively.

I also had to redraw your animation, with all the sets of pipes connected. The sudden transformation of the whole setup in the animation was too fast and too confusing to follow.
IMG_20200828_112857546_resize_0.jpg
IMG_20200828_112857546_resize_0.jpg (38.44 KiB) Viewed 3748 times
It's about as crude as could be, but seeing it all together helped make it easier to follow the sequence of events, taking place simultaneously.

At first I thought two power cylinders driving six other compression cylinders would be unrealistic, but perhaps not, with some type of active cooling, as cooling is itself a means of compression, in a way, so those cylinders might have little actual work to do.

Have you considered fluid diodes rather than valves? This seems to be an arrangement that might actually be able to make use of them, inline, as the direction of flow appears to be constant throughout the entire system.

I came up with what I thought might be an improvement of Tesla's invention. But I think I'd need a 3D printer to make one
g9Ef1Uv5fHSYA3t5APGe.jpg
g9Ef1Uv5fHSYA3t5APGe.jpg (6.28 KiB) Viewed 3748 times
Your design certainly has potential IMO, if not sheer genius. It's simplicity and complexity is rather mind boggling.

I'm also thinking some form of rotary version, Wankel type engine might be possible, similar to a rotary compressor.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

I will make drawings. It will be easier to read
I think I have designed a new type of engine and it deserves to be developed. For the moment I have only the beginning of the idea and I'm convinced that there will be evolutions in time.I would like to find an industrialist or a university that will put the financial means to develop this new type of Stirling engine.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

here are the images https://secure.digiposte.fr/p/0648f83dd ... 044c20f603
I don't know how to insert images directly into the forum posts.
I'm going to look at the Tesla's invention , it looks very interesting.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

A small precision
the top four cylinders are kept hot and the bottom four cylinders are kept cold.
there are no difficulties to insulate thermally
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

a small point that I would like to clarify again.
Stirling engines complete the cycle in one engine revolution.
With my new type of engine, the cycle is carried out with two engine revolutions. The heat transfer times are significantly increased. They have on half a revolution (180 degrees), instead of about 90 degrees, the heat transfer times are significantly increased.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

Dear Tom Booth
With openfoam I did a fast numerical modeling of the Tesla diode.
Fluid speed 7 m/s, temperature 20 degrees, air fluid.
here are the images of the result

https://secure.digiposte.fr/p/93f9604fe ... dd25ff137c

With my designed geometry, the pressure is multiplied by 3.
it's an interesting invention
Tom Booth
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Re: new concept of Stirling engine

Post by Tom Booth »

normandajc wrote: Thu Sep 03, 2020 11:59 pm Dear Tom Booth
With openfoam I did a fast numerical modeling of the Tesla diode.
Fluid speed 7 m/s, temperature 20 degrees, air fluid.
here are the images of the result

https://secure.digiposte.fr/p/93f9604fe ... dd25ff137c

With my designed geometry, the pressure is multiplied by 3.
it's an interesting invention
Is that 2D or 3D?

The fluid diodes is intended to be, in 3D circular, like a ribbed tube.

In other words, the air flow pattern would be a series of toroidal vortex rings.

If there is a 3x pressure multiplication in a 2D model, I'm curious if the effect would be greater with a 3D toroidal modeling.
Tom Booth
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Re: new concept of Stirling engine

Post by Tom Booth »

Taking a couple of the images, I'm guessing that the air flow in this image is from the left:
fluid_diode_1.jpg
fluid_diode_1.jpg (20.88 KiB) Viewed 3629 times
Then the flow is reversed?
fluid_diode_2.jpg
fluid_diode_2.jpg (22.54 KiB) Viewed 3629 times
The red indicates what? High pressure, high temperature, turbulance?

Anyway, from the images, it appears that possibly the fluid diode might work as intended.

Tesla's original design was a flat 2D type design.

https://youtu.be/6fgfr2BZUF8

In theory, it was supposed to work best where there is a reciprocating, back and forth, alternating flow.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

I used as software openscad, smathstudio and openfoam
https://www.openscad.org/ https://en.smath.com/view/SMathStudio/summary https://openfoam.org/
these softwares are free of charge
I'm going to edit my files and modify them to be parametric and I'm going to give instructions on how to modify these files.
I will prepare these files on Thursday and give these files.
It's a solid of revolution that I made and I made a cut to visualize the flow inside.
The geometry, the flow speed influence the calculation of the pressure.
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

pressure view
flow according to the x
p.png
p.png (71.85 KiB) Viewed 3623 times
pressure view
flow according to the x
p2.png
p2.png (57.16 KiB) Viewed 3623 times

revolution solid
vue.png
vue.png (72.5 KiB) Viewed 3623 times
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

read the file "read" in tesla_para
I use as software solvespace, openscad, smathstudio and openfoam

https://fil.email/lHDyM282
normandajc
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Re: new concept of Stirling engine

Post by normandajc »

geometry
1.png
1.png (30.27 KiB) Viewed 3798 times
With U=7m/s R1=22.5 mm R2=10 mm Rtub = 20 mm figure of pressure ( Pa )
p.png
p.png (63.04 KiB) Viewed 3798 times
p.png
p.png (78.9 KiB) Viewed 3798 times
With U=7m/s R1=22.5 mm R2=10 mm Rtub = 10 mm figure of pressure ( Pa )
p.png
p.png (39.47 KiB) Viewed 3798 times
p.png
p.png (46.02 KiB) Viewed 3798 times
With U=7m/s R1=22.5 mm R2=10 mm Rtub =5 mm figure of pressure ( Pa )
p.png
p.png (33.05 KiB) Viewed 3798 times
p.png
p.png (34.73 KiB) Viewed 3798 times
With U=3.5m/s R1=22.5 mm R2=10 mm Rtub =5 mm figure of pressure ( Pa )
p.png
p.png (32.64 KiB) Viewed 3798 times
p.png
p.png (31.52 KiB) Viewed 3798 times
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