@@ShanePomeroy I'm pretty sure if you set up a PayPal or some kind of way for us to give you money as some kind of form of appreciation you will definitely get some donations my income tax is coming in and I know I will definitely throw you a hundred bucks your way just for being an awesome inventor
@@ShanePomeroy I also hope that you took my speaker generator configuration into consideration ruclips.net/video/6LwMpoU-NJ4/видео.htmlsi=0d212zm43sEI7e80
Awesome! That piston wobble can be resolved with a watts linkage, it was James Watt's solution to reducing this situation in early steam engines. You really should consider trying to find a copy of that history of caloric and heat engines, sadly I gave mine away to someone like yourself but it is the bible on this subject imho.
Good Idea with the watt linkage. I have a copy of caloric and heat engines. My favourite hot air engine book. At the end of the day there isn't a great deal that hasn't already been thought of so the info contained is very relevant.
Awesome....Would love for this to become a kit for DYI ers! Looking forward to the plans being released or even selling a fully constructed unit... Will be watching the progress...
What an a amazing piece of kit! this was one of those random videos YT algo thought I might like and I have. This is the sort of thing we could do with here as we have endless wood but need a way to convert that into electricity! Many thanks, I'll go and catch up with your other build videos now.
This looks promising. The diaphragm makes as much noise as mine. I need to buy thermometers like yours. This will allow you to better track the process of converting heat into work. Regards
If you find a solution to the diaphragm noise I'm all ear's? Someone's mentioned a slight pressure charge so the diaphragm is always pushing out and does not fold in on itself.
Would efficiency be improved by trickling cold water of the cool end of the heat transfer tubes? If so, a simple pump could be used to recyle the water, without draining too much energy.
I thought it looked like it was running very well. How long will the piston membranes last. I suppose that's yet to see. I suppose like everything it's a serviceable item. Great progress and good old fashioned engineering.
Would probably increase the efficiency of the engine with a higher pressure (you'd need to pressurize the other side of the piston for it to not just be stuck at expanded) and a cooling method (either passive air or water cooling). Great and sleek engine build!
Perhaps you could use off the shelf replacement parts from a large air-operated diaphragm pump - they use large diameter pumping diaphragms much like what you've built for this engine, perhaps even the housing could be adapted to your design. Wonderful project so far my friend, thank you so much for sharing!
Hola amigos, enhorabuena, has conseguido una máquina stirling excelente, chapó, estoy deseando que acoples el generador eléctrico, cuanto pesa un el volante de inercia y el diámetro de los pistones me lo podrías decir, gracias y un saludo machote.
I haven't checked the literature, but, if you add a safety valve to control internal pressure, then rather than venting the machine during start up you could actually pressurise the system to say 1 bar. That would double the mass of the working fluid, and hence improve (maybe 'double') the output. Maybe! Then if the system is sealed mayhap optimise the working fluid. I've heard meths is quite good - what could possibly go wrong!
This is so fascinating - my mind thinks of things like the feathering mechanism found on side wheel paddle boats and Watts Parallel motion to make your diaphragm pistons go square into the receptor - I still like the corrugated mesh "finger" inserts to maximize heat transfer
Hi, I'm going to take a power reading first and then plan to insert the mesh pieces and check the power again. My fathers been down the local hardware shop checking out the edging mesh profiles for blockwork! cheers
@@ShanePomeroy Yes I imagine edging mesh profiles shape would work but are likely to be galvanized steel and less conductive - Be very careful with getting galvanized items too hot - Zinc burns in a white haze and is very toxic if breathed in - A friend ended up in hospital in an oxygen tent after volunteering to cut down a school cycle shed with a torch - Aluminum from a car grill mesh available from Fleebay would be more malleable and a better conductor - if you corrugate it slightly it will make alternate contact with the sides of the passages to stop it rattling and conduct more heat.
Wow, just when I think it's as good as it gets, you outdo yourself! Wonderful. This is a great series. And forgive me for being presumptuous, but I'm very excited to see a design like this go as far as it can. If there is one thing I would like to see, it is some regenerator wool pushed into each slot in the middle of the "cold' exchanger. Even though the current long-tube design is acting as a regenerator, the surface area is low compared to something like steel wool. I'm 99% sure you could push the output to much higher by introducing steel wool into the engine. One thing about Stirling coolers, is that they don't work well at all, unless you finely tune the regenerator performance. The same goes for engines. I've seen regenerators increase output by 2x (depends on the design and how good/bad it is to begin with).
Hi, I will add a filler of some kind along the length of the engine at some point. I'm going to take a power reading first to see where we are : ) Cheers
@@ShanePomeroy Seems like a very reasonable thing to do. I appreciate all the work you put into this. Thank you for taking the time to share it with the rest of us.
Hey Shane. I would like to see a comparison between what you have and one with a material such as metal scrubbers packed into the tubes as a regenerator. There seems to be a lot of air space between the two pistons. Also ypu my have thought of a second arm on either end to keep the piston flat moving in and out I do love the progress its fantastic
Hi Perry, I'm contemplating inserting a mesh of some sort down the tubes. In hind sight I would have reduced the 3mm air gap to 1mm or so. The dead space situation isn't actually to bad because I can still achieve 1.6 : 1 compression ratio with fairly large surface area's. The pistons could do with some stabilisation but funny enough it doesn't seem to effect the running that much so I'm not to worried. All the best
If the piston linkage was a parallelogram it would eliminate rocking. You would still have some lateral shift, but I imagine that isn’t something your looking to eradicate.
Hello Shane, It appears that this is an Alpha configuration Sterling engine. Which makes me ask why you have not piped the two cylinders together? I may be off but I believe you will see an increase in output power by doing this.
I wonder if attaching a fan on the crankshaft below the heat exchanger would improve performance any? Or would the resistance of the fan offset any gains?
Hi Mark, not a bad point. The cooler has a much harder job losing heat. I'm fairly happy with the basic configuration, so going forward this is worthy of experimentation. Thanks
Maybe a parallel linkage for the pistons? You might be able to improve cooling by funneling the cold air over the regenerator with a flue style thing above it to create a draught a bit like cooling towers for a power station, or maybe a water spray?
Good ideas! You've got me thinking, I could surround the existing chimney with an outer tube and use this convection heat to pull air over cold side. I shied away from parallel linkages due to the increased complexity, cheers
@@ShanePomeroy if you fixed a rod to the piston link, say a foot long for a random number and then supported the end of it central to the cylinder though a sleeve supported perhaps by a bracket bolted to a couple of the piston pericarp securing bolts, it should stop the diaphragm tilting but using no extra linkages. Maybe a Teflon ring or similar as the sleeve / support. Just typing out loud.
5:00 Solve one ... Since the part of the stroke where the piston is entering the support ring is very short, why not tighten the bolt on the piston-lever point so that the orientation of the piston is rigidly fixed to the lever arm. That will have the piston in the correct position on the 'bottom' of the stroke, and the minor off-parallel at the top of the stroke wont matter. Removes a moving joint which you could remove the bolt and then weld solid once the alignment was correct. Best part no part - as someone says!
Hi Nigel, I like your thinking! I'll take a look at removing that pivot, it might be fine without it? The beet part is no part - my kind of engineering! Many thanks
There's a regenerator? If not, I believe your can seal the bottom of the tubing just after the hot box and pour molten aluminum between the tubes to take some heat...
The whole thing is a regenerator - dividing it up into a stack of 8 parallel channels (more would be better I imagine, but only to a point) allows for greatly increased surface area without increased volume, providing the same benefit as a more conventional regenerator.
theoretically I think the engine would use more energy than it put out. Practically the diaphragms will burst. It is a good question because I don't fully understand the principle's here. I've seen engines that run very high compression ratio's but is this because they are running high temperature differentials? All the best
Very interesting this is a similar configuration for a cryo cooler which is a highly efficient Sterling engine you're on the right track I would suggest a speaker generator and frame integration as a part of the diaphragm refinement another words you can add a speaker generator at the ends of these pistons/ diaphragm in order to generate a large amount of electricity depending on what subwoofer you are using ruclips.net/video/psfzTCVWtGc/видео.htmlsi=0ldBQITFalgqTqs_
@@ShanePomeroy I love your alpha stirling engine by the way. It reminds me a lot of another one i seen on you tube titled "Stirling Engine Alpha Monochannel" by Alexandr Fediaev Iron makes a fairly good regenerator material as it offers one of the highest volumetric heat capacities forr the surface area containing that material and the dead space it contains. Your heat exchanger and stirling regenerator channels are better than Alexandr's in that yours probably creates less turbulence, and is easyer to make. Maybe his design might inspire you to make a tub for water on the cold side of your engine. It would have better thermal energy transfer capability than air and could be cycled through a larger radiator. Motor spinning one way moves heat into your chimney, and removes heat if spun the other way.
@@kreynolds1123 I have seen alexandr 's stirling enyine : ). It certainly must have inspired me with this engine. I was trying to stay away from cooling water to cut down on complication. Interesting fact about iron's heat capacity. I can also see how cold I can make my engine (heat pump!). Many thanks
@@ShanePomeroy i have some time to kill, and hope to convey to anyone reading this, why volumetric heat capacity is important in a stirling regenerator. Take iron. It has a specific heat capacity of 0.451 J/g•°K and a density of 7.874 g/cm³. Thus it's volumetric heat capacity = density × specific heat capacity, so 1cm³ of iron stores about 3.55 (J/cm³⋅K). We might contrast that with 1cm cube of Polypropylene with a volumetric heat capacity of about 1.9 (J/cm³⋅K). Now if both cubes are shredded to the same surface area with both having 1cm³ dead space for air flow, then which would you prefer? 3.55 (J/1cm³ of iron + 1 cm³ of air ⋅K) or 1.9 (J/cm³ of Polypropylene + 1cm³ of air ⋅K)? Given the fact that I can store more energy for the same surface area means I can use less surface area to store the same energy, I'd be more interested in iron. Steel wool is made from low carbon steel with about the same volumetric heat capacity as pure iron, while stainless steel wash scrubs are made from 304 stainless steel which as a better volumetric heat capacity of 3.89 - 4.28 J/cm³⋅K, and are already shredded. But more impressively, the thermal conductivity of 304 stainles steel is roughly 1/3 that of iron which reduces conduction from the hot chamber to the cold chamber. Making 304ss a very desirable regenerator material, but less desirable for the hot and cold thermal exchang material. 304 ss wash scrubs or screen meshes make effective regenerator material that have also has better resistance to oxidation.
Hi, many thanks for that. I'm more of a practical hands on person myself so I'm always interested in the theory being explained to me in simple terms, All the best@@kreynolds1123
@@ShanePomeroy awesome i would love to see a trackor that runs on a stirling engine, By the way would it possible if you could email the drawings or cad files, of the engines. As i would like to build one.
Brilliant piece of homemade engineering. You deserve some financial reward from the sale of plans/parts/kits.
yeah, even for a low output engine these are of interest for the homesteading and off grid communities
I only really do it for fun : ) I've got a day job! It would be nice to see a kit widely available. Just a bit more refining to do
@@ShanePomeroy I'm pretty sure if you set up a PayPal or some kind of way for us to give you money as some kind of form of appreciation you will definitely get some donations my income tax is coming in and I know I will definitely throw you a hundred bucks your way just for being an awesome inventor
@@ShanePomeroy I also hope that you took my speaker generator configuration into consideration
ruclips.net/video/6LwMpoU-NJ4/видео.htmlsi=0d212zm43sEI7e80
@@ShanePomeroy can I ask what you timed this one at?
As soon as I heard you say, "Solve one problem, cause another," I thought exactly what you followed up with.
Congratulations Shane. The new engine runs well.
This is professional level craftsmanship right here my friend
This is so good. Well done Shane! Great progress.
That is what I call a stick to itiveness You've got it mate
Looks awesome
Excellent work as always
Thank you for sharing
I just asked the reddit stirling engine community to follow you if they aren't. Keep up the good work!
Could you give the link to this community?
@@borisroca4633 search
r/stirlingengines
Awesome! That piston wobble can be resolved with a watts linkage, it was James Watt's solution to reducing this situation in early steam engines. You really should consider trying to find a copy of that history of caloric and heat engines, sadly I gave mine away to someone like yourself but it is the bible on this subject imho.
Good Idea with the watt linkage. I have a copy of caloric and heat engines. My favourite hot air engine book. At the end of the day there isn't a great deal that hasn't already been thought of so the info contained is very relevant.
Awesome....Would love for this to become a kit for DYI ers! Looking forward to the plans being released or even selling a fully constructed unit... Will be watching the progress...
What an a amazing piece of kit! this was one of those random videos YT algo thought I might like and I have. This is the sort of thing we could do with here as we have endless wood but need a way to convert that into electricity! Many thanks, I'll go and catch up with your other build videos now.
This looks promising. The diaphragm makes as much noise as mine. I need to buy thermometers like yours. This will allow you to better track the process of converting heat into work. Regards
If you find a solution to the diaphragm noise I'm all ear's? Someone's mentioned a slight pressure charge so the diaphragm is always pushing out and does not fold in on itself.
Thank you Shane! Nice work.
Chuck in Florida.
Brilliant! cant wait for the next developments!
Well done, brilliant. I could listen to that sound all day. It is so interesting I have subscribed. Phil.
That is so great. It's been really cool watching the improvements you make with each iteration.
Brilliant she was just smacking along.Yes if you run a fan off it to cool her. A funace fan in the design.
Wonderful video.
Thank you for taking your time to share this.
Would efficiency be improved by trickling cold water of the cool end of the heat transfer tubes? If so, a simple pump could be used to recyle the water, without draining too much energy.
아주 멋있습니다
Fantastic machine!
Great job!
Un grand BRAVO de France
Excellent video engine goes like the clappers now. Keep up the good work. Let us know when those plans or kits available
Brilliant work!
Put an alternator on it and charge batteries!
I thought it looked like it was running very well. How long will the piston membranes last. I suppose that's yet to see. I suppose like everything it's a serviceable item. Great progress and good old fashioned engineering.
Just got this video offered by RUclips.
I think you may need to balance it, however it is awesome!
Yes, your right : )
Would probably increase the efficiency of the engine with a higher pressure (you'd need to pressurize the other side of the piston for it to not just be stuck at expanded) and a cooling method (either passive air or water cooling). Great and sleek engine build!
Good job mate, nice engine.
Id love to purchase a kit or Atleast the plans so I can have them cut here locally. Great job!
Perhaps you could use off the shelf replacement parts from a large air-operated diaphragm pump - they use large diameter pumping diaphragms much like what you've built for this engine, perhaps even the housing could be adapted to your design. Wonderful project so far my friend, thank you so much for sharing!
Those large air-operated diaphragm pump are actually the inspiration for this engine. I will check the prices out, thanks
Awesome stuff - looks like with a few tweaks it could almost be there 👍👍
Жирный лайк разработчику, это действительно впечатляет, кто сказал,что стирлинг не эффективен? Респект вам
Put a spring between the Piston arm and the Piston were put your hand, to help with the Piston wobble…..
Parallel linkage would give linear motion to bellows but more complexities to factor into design
Hola amigos, enhorabuena, has conseguido una máquina stirling excelente, chapó, estoy deseando que acoples el generador eléctrico, cuanto pesa un el volante de inercia y el diámetro de los pistones me lo podrías decir, gracias y un saludo machote.
Flywheel is about 40kg and diameter of pistons is about 12". I'll put the full spec in the description when I get it together
@@ShanePomeroy gracias, amigo, seguro que te seguiré haciendo más preguntas.
I haven't checked the literature, but, if you add a safety valve to control internal pressure, then rather than venting the machine during start up you could actually pressurise the system to say 1 bar. That would double the mass of the working fluid, and hence improve (maybe 'double') the output. Maybe! Then if the system is sealed mayhap optimise the working fluid. I've heard meths is quite good - what could possibly go wrong!
Much smoother running now.
Also use a flexible clothes dryer duct to move cool air over the tubes!
Have you measured the running temperature of the fire chamber and what is it? This is amazing and I thank you for sharing your progress.
I will take some readings before / after the hot heat exchanger and also internal temps too, kind regards
This is so fascinating - my mind thinks of things like the feathering mechanism found on side wheel paddle boats and Watts Parallel motion to make your diaphragm pistons go square into the receptor - I still like the corrugated mesh "finger" inserts to maximize heat transfer
Hi, I'm going to take a power reading first and then plan to insert the mesh pieces and check the power again. My fathers been down the local hardware shop checking out the edging mesh profiles for blockwork! cheers
@@ShanePomeroy Yes I imagine edging mesh profiles shape would work but are likely to be galvanized steel and less conductive - Be very careful with getting galvanized items too hot - Zinc burns in a white haze and is very toxic if breathed in - A friend ended up in hospital in an oxygen tent after volunteering to cut down a school cycle shed with a torch - Aluminum from a car grill mesh available from Fleebay would be more malleable and a better conductor - if you corrugate it slightly it will make alternate contact with the sides of the passages to stop it rattling and conduct more heat.
Wow, just when I think it's as good as it gets, you outdo yourself! Wonderful. This is a great series.
And forgive me for being presumptuous, but I'm very excited to see a design like this go as far as it can. If there is one thing I would like to see, it is some regenerator wool pushed into each slot in the middle of the "cold' exchanger. Even though the current long-tube design is acting as a regenerator, the surface area is low compared to something like steel wool. I'm 99% sure you could push the output to much higher by introducing steel wool into the engine. One thing about Stirling coolers, is that they don't work well at all, unless you finely tune the regenerator performance. The same goes for engines. I've seen regenerators increase output by 2x (depends on the design and how good/bad it is to begin with).
Hi, I will add a filler of some kind along the length of the engine at some point. I'm going to take a power reading first to see where we are : ) Cheers
@@ShanePomeroy Seems like a very reasonable thing to do. I appreciate all the work you put into this. Thank you for taking the time to share it with the rest of us.
Hey Shane.
I would like to see a comparison between what you have and one with a material such as metal scrubbers packed into the tubes as a regenerator. There seems to be a lot of air space between the two pistons.
Also ypu my have thought of a second arm on either end to keep the piston flat moving in and out
I do love the progress its fantastic
Hi Perry, I'm contemplating inserting a mesh of some sort down the tubes. In hind sight I would have reduced the 3mm air gap to 1mm or so. The dead space situation isn't actually to bad because I can still achieve 1.6 : 1 compression ratio with fairly large surface area's. The pistons could do with some stabilisation but funny enough it doesn't seem to effect the running that much so I'm not to worried. All the best
Brilliant thanks for sharing
Mate great job running loads better, get some magnets stuck to that Flywheel and some stationary coils..
Skip the magnets and get a big lazy susan to make a Wimshurst generator, connect it up to an arcing tower and you are talking kilowatts. ;-)
@@christopherd.winnan8701 kilovolts or kilowatts big difference are you sure???...
@@christopherd.winnan8701 Wimshurst's generator produces kilovolts, but hardly any real power
If the piston linkage was a parallelogram it would eliminate rocking. You would still have some lateral shift, but I imagine that isn’t something your looking to eradicate.
Well done mate!
Thank you.
You shoukd be really proud
Hello Shane,
It appears that this is an Alpha configuration Sterling engine.
Which makes me ask why you have not piped the two cylinders together?
I may be off but I believe you will see an increase in output power by doing this.
Excellent work Shane. I am wondering how many degrees the pistons are out of phase? 90 deg? Also I'm avidly awaiting the power output results!
Hi Greg, I've set the phase angles at 105 degrees. Power test in a few weeks once I've sorted a dynameter. Don't expect massive power!
Wow awesome! Runs well, how long will the diaphragms last? Will you get a good lifespan out of them you think?
Not sure yet, time will tell : )
I wonder if attaching a fan on the crankshaft below the heat exchanger would improve performance any? Or would the resistance of the fan offset any gains?
Good idea and good question : )
amazing
Looking good! But why aren't you actively cooling the cold side?
I'm experimenting with air cooling to try and reduce complexity, just to see : )
Wonder if tapering the cooling tubes would help to displace the heat faster giving more surface area.
Hi Mark, not a bad point. The cooler has a much harder job losing heat. I'm fairly happy with the basic configuration, so going forward this is worthy of experimentation. Thanks
Your a Damm genius
No, just a madman with to much spare time! cheers
Maybe a parallel linkage for the pistons? You might be able to improve cooling by funneling the cold air over the regenerator with a flue style thing above it to create a draught a bit like cooling towers for a power station, or maybe a water spray?
Good ideas! You've got me thinking, I could surround the existing chimney with an outer tube and use this convection heat to pull air over cold side. I shied away from parallel linkages due to the increased complexity, cheers
@@ShanePomeroy if you fixed a rod to the piston link, say a foot long for a random number and then supported the end of it central to the cylinder though a sleeve supported perhaps by a bracket bolted to a couple of the piston pericarp securing bolts, it should stop the diaphragm tilting but using no extra linkages. Maybe a Teflon ring or similar as the sleeve / support. Just typing out loud.
5:00 Solve one ... Since the part of the stroke where the piston is entering the support ring is very short, why not tighten the bolt on the piston-lever point so that the orientation of the piston is rigidly fixed to the lever arm. That will have the piston in the correct position on the 'bottom' of the stroke, and the minor off-parallel at the top of the stroke wont matter. Removes a moving joint which you could remove the bolt and then weld solid once the alignment was correct. Best part no part - as someone says!
Hi Nigel, I like your thinking! I'll take a look at removing that pivot, it might be fine without it? The beet part is no part - my kind of engineering! Many thanks
First class 😎
Hello !
Add some positive pressure, and add some rubber band between conrods to negate sub-optimal buffer pressure.
Positive pressure is a top idea to stop the diaphragms collapsing in on themselves.
5:11 Best cooling would be water mist. You need only 1,6L of water to cool off a kilowatt-hour of heat. It's called an open circuit cooling.
I'll look into that, many thanks
Cool project. I think you misread the pressure gauge, it hit 6psi (0.4 bar not 0.6 as you said)
Your quite right! My bad! I've just spun it over to check. It does bear the question if I should increase the ratio now? thanks
Having accurate numbers can only help 😊 I've misread a few things in my time...
With a bit of modification to the flywheel, it could be made ventilate the cold side heat exchanger.
It is a good idea. I suspect I will probably do this in time, cheers
How powerful it is? Seems like 300 watts at least
I'll test it over the coming weeks : )
5:39 these have good visual because they fall off as the temperature hits the Curie point.
There's a regenerator? If not, I believe your can seal the bottom of the tubing just after the hot box and pour molten aluminum between the tubes to take some heat...
The whole thing is a regenerator - dividing it up into a stack of 8 parallel channels (more would be better I imagine, but only to a point) allows for greatly increased surface area without increased volume, providing the same benefit as a more conventional regenerator.
How come these magnetic temperature gauges do not loose their magnetic potential with heat?
Good question, I've just taken a look at one! Turns out the magnet does not touch the heated surface and is held off a few mm so there is an air gap.
What if compression ratio increase to 10:1 or more?
theoretically I think the engine would use more energy than it put out. Practically the diaphragms will burst. It is a good question because I don't fully understand the principle's here. I've seen engines that run very high compression ratio's but is this because they are running high temperature differentials? All the best
Спасибо за ваш труд! Вы ИНЖЕНЕР! Я Вам хотел предложить расширить камеры для увеличения ресурса манжет.
how much HP is this?
Very interesting this is a similar configuration for a cryo cooler which is a highly efficient Sterling engine you're on the right track
I would suggest a speaker generator and frame integration as a part of the diaphragm refinement another words you can add a speaker generator at the ends of these pistons/ diaphragm in order to generate a large amount of electricity depending on what subwoofer you are using ruclips.net/video/psfzTCVWtGc/видео.htmlsi=0ldBQITFalgqTqs_
whats power output
I don't care how slowly it moves, I want to see it drive somewhere
lol, me to : )
I'm curious if you would like to try it as a stirling heat pump rather than a stirling engine.
Hi, it would be a fun experiment. I've got a small motor I could rig up.....
@@ShanePomeroy I love your alpha stirling engine by the way. It reminds me a lot of another one i seen on you tube titled "Stirling Engine Alpha Monochannel" by Alexandr Fediaev
Iron makes a fairly good regenerator material as it offers one of the highest volumetric heat capacities forr the surface area containing that material and the dead space it contains.
Your heat exchanger and stirling regenerator channels are better than Alexandr's in that yours probably creates less turbulence, and is easyer to make.
Maybe his design might inspire you to make a tub for water on the cold side of your engine. It would have better thermal energy transfer capability than air and could be cycled through a larger radiator.
Motor spinning one way moves heat into your chimney, and removes heat if spun the other way.
@@kreynolds1123 I have seen alexandr 's stirling enyine : ). It certainly must have inspired me with this engine. I was trying to stay away from cooling water to cut down on complication. Interesting fact about iron's heat capacity. I can also see how cold I can make my engine (heat pump!). Many thanks
@@ShanePomeroy i have some time to kill, and hope to convey to anyone reading this, why volumetric heat capacity is important in a stirling regenerator.
Take iron. It has a specific heat capacity of 0.451 J/g•°K and a density of 7.874 g/cm³. Thus it's volumetric heat capacity = density × specific heat capacity, so 1cm³ of iron stores about 3.55 (J/cm³⋅K).
We might contrast that with 1cm cube of Polypropylene with a volumetric heat capacity of about 1.9 (J/cm³⋅K). Now if both cubes are shredded to the same surface area with both having 1cm³ dead space for air flow, then which would you prefer? 3.55 (J/1cm³ of iron + 1 cm³ of air ⋅K) or 1.9 (J/cm³ of Polypropylene + 1cm³ of air ⋅K)? Given the fact that I can store more energy for the same surface area means I can use less surface area to store the same energy, I'd be more interested in iron.
Steel wool is made from low carbon steel with about the same volumetric heat capacity as pure iron, while stainless steel wash scrubs are made from 304 stainless steel which as a better volumetric heat capacity of 3.89 - 4.28 J/cm³⋅K, and are already shredded. But more impressively, the thermal conductivity of 304 stainles steel is roughly 1/3 that of iron which reduces conduction from the hot chamber to the cold chamber. Making 304ss a very desirable regenerator material, but less desirable for the hot and cold thermal exchang material.
304 ss wash scrubs or screen meshes make effective regenerator material that have also has better resistance to oxidation.
Hi, many thanks for that. I'm more of a practical hands on person myself so I'm always interested in the theory being explained to me in simple terms, All the best@@kreynolds1123
I’m going to watch this very closely…
You Should next try to build a Stirling engine tractor like this one - ruclips.net/video/NbZji_my4Kw/видео.html - And drive it around the street.
I really, really want to but I am still caught up trying to design a fairly decent engine! When I am happy, I'll start building silly vehicle's!
@@ShanePomeroy awesome i would love to see a trackor that runs on a stirling engine,
By the way would it possible if you could email the drawings or cad files, of the engines. As i would like to build one.