KTA18 Thermoacoustic Stirling engine

[unclekju]

below the glass tube What is

[prayfortruejustice]

How many of these do you have? They are really nice.

[bambi186]

what is the puffy material?

[ScienceHobby24]

how would you go about making the piston?, i hear graphite is the best, but how did you go about making yours?

[chrisdude1001]

@ScienceHobby24 idk about this guy but i would use a lathe

[drkggjh]

great engine

[raidfibre]

That's a pretty nice looking model but it's not a thermoacoustic stirling it's just a stirling with no displacer.

[stirlingsteamboy08]

I LIKE THE ONES WITH MARBLES IN sell them on ebay

[stirlingsteamboy08]

you got these on ebay and the twin cyillinder ones BUT THEY ARE TO DEAR THERE ONLY WORTH ABOUT 60£

[popupwool]

What is the heat source under the tube?

[chrisdude1001]

@popupwool its running on a meths/denatured alcohol burner

[adrianTNT]

Why? You need a flame under your thing to get started too?

[chrisdude1001]

@adrianTNT because it heats the air causing it to expand

[kisuke17]

some one tell me if i am way of or what ever but

does it work by :1rst air is heated causing it to expand in the chamber then the pressure needs to be relieved so it pushes the piston back. then rotational force spins the wheel forcing the piston back piston the air flow then gets re pressurized and is pushed back again completing a stroke

i pretty much know this is wrong i just would like to know where my logic is off unless its right then yaaaaahhhhh

[sunwindwaterenergy]

Acoustic- meaning sound waves..thermal acoustic- meaning thermal waves or temperature heat waves not sound..ie heating /cooling waves of air= movement.

[fmflores2000]

Pls. tell me where can I buy this good conversation piece of device. I will put it on my table

[stirlingeezer]

Heat is supplied with a small spirit burner.

Applying the heat at a specific point along the tube sets a high frequency sound wave bouncing up and down the tube. Variations in pressure and velocity caused by this wave act on the piston, ultimately giving rotation.

[PalmRunner]

I don't think the sound has something to do with this engine. The tube is a way to short to maintain a resonance at ~10Hz (600rpm).

[richphuk]

The sound isn't related to the tube length in this demo because the end is not open, however it is still considered an acoustic device because there is a resonance. The gas goes to one side and heats up and expands, then it touches the cold side and contracts. No moving parts regulate the cycle, thus acoustics.

[PalmRunner]

The steel wool works mainly as a heat exchanger rather as a regenerator. The cold end of the engine is the piston/cylinder side, not the closed tube end!

[PalmRunner]

When the piston moves towards TDC, the cold air expelled from the cylinder is compressed in the hot chamber. The air gets heated and expands pushing the piston towards BDC. The hot air is now inside the cold cylinder. It is cooled and contracts and pulling the piston back towards TDC. The cycle then repeats. The flywheel momentum helps the piston to overcome the dead centers. No acoustics is involved!

[richphuk]

I think its called thermoacoustic because of it's similarity to the organ pipe.

[PalmRunner]

I think the name comes due to the visual similarity with a demo kit sold as "thermoacoustic laser". Use google to search for "los alamos engine" to learn about real thermo-acoustic engines.

[dvandy83]

What you are describing is a regular Stirling engine. This is a link to how a thermoacoustic stirling engine works: americanscientist . org, type in "thermoacoustic stirling engine" and click on "power of sound". page 5 is the critical page

Are you trying to say that the engine in this video is not a TSE, but rather a regular stirling engine? Are you sure? How do you know this?

[PalmRunner]

Thermo-acoustic engine has also stirling cycle, but this one is not thermo-acoustic. It's not really a regular stirling due to the absence of displacer. I have build one myself and meanwhile have read a lot. Better name would be thermal lag engine. For more information refer to patent No 5414997

[fldz]

I'm a complete noob to this, (& most science) but I would expect some kind of harmonic resonance that would make 'sweet-spots' in RPMs. If it is acoustic, would small changes in distance have big effects on RPMs?

[squarestuff]

i dont understand.  how does it work?

[psarofim]

where is the heat coming from?

[DrCahill]

I'm slightly confused by the mechanics of this stirling engine. I see a glass tube with stainless steel mesh in the bottom and a power cylinder. Is that everything?

[LeoDJ1992]

Yes