I show several ways to improve the efficiency and power of these simple engines. Lindy's video: • Stirling Engines - the... Help me make videos by donating here: / codyslab
The number of times I watch one channel to find that they also subscribe to a number of other channels that I watch. Great minds think alike - I think! :-)
pered5 Energy doesnt make black holes. A large amount of matter collapsed in a small area of space. In order for energy to make a black hole you'd need the energy to transform into matter, abd even though E=MC^2 we have never been able to make a large amount of matter from energy, (or any at all to my knowledge)
A FYI from that i got from thermodynamics studying in college. A colder cold-source is more efficent than a hotter heat-source. That is, you will get more power if you decrease the cold source 5º than if you increase the heat source 5º.
Math. And Algebra. Can't remember the exact formula explanation, it was pretty long. But, my physical explanation for it is, probably because the cold source (being colder) has more density of mass that can transfer heat out of the system. The heat source has less mass density and therefore is less efficient at transfering heat into the system. IE. the cold source can absorb energy faster than the heat source can put into it. Making cold more efficient at creating a bigger temp difference.
I don´t think so. Eff=1-T1/T2 where T1 stands for the cool source, and T2 is the hot one. So you gotta make the difference as big as you can if you want efficiency
I'm really glad you linked to lindy beige. he has a great channel and makes really good content, so I'm really glad to see you supporting him! I think I first some him through you or an AVE cross link. I just really like knowing all the engineering and science RU-vid channels follow and support eachother. it's really encouraging!
Cody: "I hope I'm not bothering the fish." Fish: "OMG, we are going to be part of an experiment! We're all gonna die! RUN! RUN FOR YOUR LIVES!!!" OR Fish: "Oh wow! What is this spinny thing? Is it food? Why is it ticking? I can't eat it! Don't torture us, oh Great Wanderer of Land!"
Nate Smith and that would matter why? An increase in voltage? Just nope. Voltage doesn't pile up. This engine in this setup would eventually even slow down because the atmosphere in the bottle will heat up, decreasing tbe temperature difference for the engine.
The reason why they were swimming back and forth was because they were courting, based on their behavior i can tell that they are 2 males and a female, and they are in heat. So the way they were acting it's not related to the experiment itself. Now if the experiment was safe for the fish or not, that's a different discussion.
It's astounding how interconnected all the cool channels seem to be. I've watched Lindy's vids for years, I found your channel through watching Isaac Arthur and now I see a vid where you reference Lindybeige's channel.
Geez dude. I've never watched one of your videos without learning something new... Thanks a lot for all your input in your videos. you'd be an excellent teacher if you ever choose to be one
Side note: due to the fanning motion of the wheel the heavier gasses will not settle at the bottom. There will be an even mixture of what ever gasses are in the bottle.
I rewatched Lindy's video, and when I returned, the app picked up where I left off, with you saying "now that you're caught up to speed..." Surprised me haha
the PV diagram shows that doubling the pressure should double the power. and since electrical power is proportional to voltage squared you should expect the second voltage to be roughly sqrt(2) or 1.41 times the first voltage. so 0.745 V / 0.520 V = 1.43 .... seems to check out!
I think the speed of the engine would also be proportional to the sqrt of the power. so measuring the speed at twice the pressure it should be 1.41 times as fast as at normal pressure.
Checks out a bit too well IMO, doesn't account for friction in various parts of the engine as Cody points out in the video - these would really not be negligible in this scenario.
About the time you made this video, I bought one exactly like it, off ebay. When it arrived, I replaced the stainless steel plates with aluminum, 1/16th inch, which doubled the rpm at least. I've played with many versions of this engine, from superheated, and cooled, to the simple "atmospheric" as this one, their best feature is their simplicity of design, and of driving needs, they are simply not "torque monsters" in any way, shape or form, but do very well with simple basic tasks such as pumping water from a mine, day and night, minimal service and maintenance. We've jumped past a great many basic engine designs that are perfect for specific tasks, because we tend to leap on "new", with little debate on "effective". These have great potential in any situation where one has differential temperature, and a "constant, low load engine need". The issue is one of choosing the application to meet the facts, not changing the situation to meet the needs of an engine. Most people don't know, we operated Newcomen's steam condensing engine, as most effective until the idea of wrapping music wire around a wrought iron boiler, allowed for a pressure engine, designed by James Watt, a century later. Most of our technology has come into its own, only when another technology makes it possible to do things vastly different, as "Bessemer steel" made possible high speed steam, and ultimately, diesel and gas engines. I've played with "atmospheric engines", flamesuckers, for many years, because they make great gifts, but first, because I found I could see the actual anular flow of gases, watching the action of the flame, "external combustion", sucked into the cylinder, something air, in a flow bench, with colored smoke, can only begin to show. I have long enjoyed your delving into the exotic, strange, and the general organic chemistry. Thanks for some really interesting work.
Hey Cody you should get some clear acrylic pipe and unscrewable endcaps and put a valve stem on it it would allow you to put way more pressure and show just how much power you could get
Hi Cody, how about building one on top of a compost bin and using the composting process as a heat source? It'd be a great recycling example! Thanks for the video it was awesome!
I have always wondered if Stirling Engines can be used to harness energy from heat (which is lost energy) in many devices, essentially converting the heat into energy and keeping it in a loop
there are two problems with this one, a stirling engine will eventually stop moving even though heat is being produced, because heat will creep into the rest of the engine through the base, and it relies on a temperature differential between the base and the rest of the engine in order to run. the greater the difference in temperature between the base and the rest of the engine, the faster the engine goes. for this reason, in addition to just stopping eventually, the conversion will get less efficient the longer it runs. the other issue is that stirling engines don't actually generate that much torque, and harvesting electricity from rotational movement steals rotational energy from that movement, requiring yet more torque to keep the thing spinning. these are the same reasons you can't have an electric car charge its own battery from the spinning of its wheels while it's driving - that would create a perpetual motion machine if it were possible.
Hi Cody Love the video. One thing to understand the power output of the engine. This can be done by adding various loads (resistors) until the voltage starts to drop from the 1 V you measured. At that point measure the max current while 1 V output and measure the load amount. Now you know max power output. One step further is to know the efficiency. How much power in vs power out. Love you videos thanks for sharing. 😊
I just had thermodynamic lessons in my physics class And God, I wish our teacher could do/show experiments so that we could understand sooner! Now everything makes sense, Thanks a lot Cody
You should see how fast you can make the stirling engine go by putting the base in liquid nitrogen and heating up the other side with whatever the hottest thing you can use that won't damage it is.
yeah, I know that, but i'd still like to see it try, maybe you could get it working with a really high pressure differential? Your vacuum chamber isn't perfect, after al
Thanks for sharing this great video with us. Replacing the mechanical piston engine with a piezoelectric transducer altogether, harnessing a solar-driven thermoacoustic power, is the future. All the He-pressurised vessel will not be more than a tube, quite similar to those used to hold cigars. Willing to partially sponsor a small project for that, if you fancy getting your hands dirty! Few images are put together if you like sending them to you, for clarity.
The Crow like a feedback loop. Put energy in to produce energy in the engine and have the energy produced to go back into the heating coil so that it becomes a little less reliant on the energy you put in. Rinse and repeat. Although I think the heat might become too much for the engine to use for the same reason Cody stated where a lot of heat is lost.
That's actually really cool. Good job. I suppose this could work on larger Sterling Engines as well. You could heat it with a waste oil burner. There is a lot of heat available from those and I suspect you could get a lot of energy from it - not just to make electricity but to heat water in your hot water tank or radiant floor heating - whatever.
Well that's blows Lingyb`s theory of how they work out of the water. Well done Sir! I have run my Ross yoke Stirling for 13 hours on 1cup of boiling water.
Hey Cody. I heard about a something called Peltier Module which seems to be sort of a ''solid state Sterling engine''. I don't know a lot about it and it'll be nice if you could make a video about it as well.
Omer Magen peltier units use the same principle, the difference between temperatures on either side of it but I've heard it's not efficient at converting heat energy to electricity or cold energy
Keenan Smith Peltier junctions are extremely inefficient, I'm not sure how they compare to Stirling engines though. Also, there is no such thing as "cold energy".
Peltier elements reach about 1% or slightly over at their near melting point, they are great for small packaging and having no moving parts, but unless used merely as a minor power recovery device while heating something else there isn't much point. Stirling engines are predicted to possibly reach 50% power conversion, but we are talking extremely refined, insanely high pressure, several thousand degree type of devices. These toy ones only get a couple percent efficiency, some will only really turn themselves and nothing else.
MsSomeonenew I heared that the Peltier module is used on some space probs such as Juno and the Voyager crafts. As those probs get very far away from the sun they need an alternative energy source. Using a piece of plutonium (which gives off heat) surrounded by Peltier elements, they are able to generate enough electricity for the prob's equipment.
Excellent demonstration, and patience Cody! There are another couple of other factors - the surface area of the heat exchanger could be increased a lot using fins like a heat sink, preferably with a flow path to help the most gas to heat up/cool down. A smooth cylinder isn't going to be as effective as a rough or ribbed surface designed to maximize heat transfer. In addition to density and viscosity, different gases also have different heat capacities and conductivities so these will affect performance to some degree. Helium has a very low viscosity, but it also has a high heat capacity and thermal conductivity so it can absorb and release energy more quickly. It should be an ideal gas, if it didn't want to keep escaping to space forever... It would be interesting to see how hydrogen and the other noble gases perform.
It won't run in a perfect vacuum for the reasons given, but a better question of similar taste is: At what pressure does it stop running? How high above sea level does a Stirling Engine work? Incidentally, the radio-thermal generators used in space probes are also based on thermal differentials, I guess the power output of those is limited by either black body thermal or your willingness to pack some kind of coolant? It's weird to remember that space isn't as "cold" as you'd think because there's so little thermal loss.
Cody you seemed to ignore that the atmosphere inside of that bottle will heat up due to your heating wire. The cooling side of the sterling engine will also heat up and your temperature difference will drop. You might want to install some cooling mechanism for the "cold side" of your engine. If you ever build a large scale sterling engine you also should install a cooler. If you are in possession of some constantly cool groundwater for example you should use a watercooling. Again i want to point out that a sterling engine is an incredible engine with a high efficiency (if build well) but the relative low pressure difference compared to other combustion engines and the limited time to cool your working gas at high speed due to the missing gas load exchange, leeds to a really low power:weight ratio of such engines. We use a lot of sterling engines in germany combined with our home gas heatings. But those relatively heavy and large engines in stationary work have but a few horsepowers. Normally they generate about .5-2 kW electricity. The torque of sterling engines is pretty low, so that you have to run them at a high speed to gain the needed power, leeding to even less time for the heat exchange. Also one of the biggest issues why sterling engines aren't used in large scale is because you can't use any kind of lubricant like motoroil inside of the engine. You can't lubricant your pistons etc.so they tend to stuck and break at high revolutions. This makes it quite impossible to build engines in a realistic scale with a useful power output to run electrical engines etc. You always need high capacity batteries as a buffer. Nevertheless i really look forward to your large scale sterling engine! Please build one.
Nope, it will only spend more energy moving gasses in the machine, not producing engergy. You can get the energy out in high speed or more torque. But it is still the same amount of energy.
Yes, it would since now less energy is wasted shifting gases around, its the reason it goes faster. The top speed is the speed at which the energy wasted per a cycle is equal to the energy generated per a cycle, if you were to reduce the waste you increase the max speed. The max speed comes about due to friction and other time dependant functions. Cody should have loaded the stirling engine to give a better demonstration, he assumed that was obvious though.
To my understanding, Stirling engines are sealed, there is a fixed amount of working fluid or gas inside. So changing the gas in the bottle should not change the gas in the engine, it should be air. Unless I am missing something?.
