Van de Graaff generator: device, principle of operation and application. Van de Graaff generator: device, principle of operation and application Producer of a professional van de Graaff installation design

The Van De Graaff Generator is one of those devices that will help the hitman intimidate the natives with high-voltage electrical discharges.
At the input - muscular strength, at the output - artificial lightning, everything seems to be fine.

However, it has its own characteristics, and it is precisely these features that do not allow it to be recommended for construction in antiquity ...

The principle of operation of the Van De Graaff generator is simple. We have a dielectric tape that rotates between two rollers. From below, the tape is electrified by brushes, and from above the charge is removed from it into a metal sphere. The charge accumulates on outer surface sphere, which allows you to continue to remove electrostatics from the tape from inside the ball. As a result, a discharge of about 80 kV can be accumulated. This device was invented by Van de Graaf in 1929.
But two years later, the generator was improved - it began not only to remove the charge from the tape, but a high voltage of 50 kV was applied to the tape, which made it possible to obtain one and a half million volts at the output, which was necessary for physical experiments in those days. Actually, since then these generators have been built in this way - not as generators, but as multipliers.
The discharge voltage depends on the length of the tape and on the size of the sphere. But both have their limitations—the discharge spreads in the ribbon, while it escapes from the sphere through a corona discharge. Therefore, you should neither build too long a tape, nor make a sphere too large.

As you can see, everything is simple.
Such a generator can be built long before the specified date.
But let's compare the Van De Graaff generator with . It is from the point of view of construction in antiquity.

1. Van de Graaff requires dielectric tape. In reality, it was rubber. You can use silk. Now there are also various synthetic fabrics that are electrified. And the better they are electrified, the greater will be the discharge in the generator.
Accordingly, if you have natural fibers, then the discharge will be penny, if at all. For example, I doubt that anything will work with a linen stripe.
Something will turn out with wool, but here - the smoother the fiber of the wool, the better the discharge. In ancient times, wool was very coarse, so the result will be the same.
Also, please remember that if the atmosphere is humid (some kind of Mediterranean), then even with good wool you will not get anything.

I recommend to think about the price and availability quality fabric in ancient times.
And also about the fact that a tape made of natural fabric wears out very quickly - not only will it quickly stretch between two rollers, but constant contact with brushes will shag the fabric, wear will increase by an order of magnitude. At the same time, it is desirable to twist as quickly as possible, and this speeds up the wear of the fabric (I suspect that they will accelerate even non-linearly). In addition, such use leads not only to frequent replacement of the fabric, but also to the regulation of the distance between the rollers, because if the fabric sags a little, the rollers will scroll idle (rubberized rollers will not be available).
Anyone who has tried to build self-made Van De Graaffs should remember that the fabric is made of synthetic fiber will be inaccessible, and the rollers will be wooden and sliding.

2. As is clear from the design, instead of one shaft in the electrophore machine, we will have two here, and the distance between them will have to be constantly monitored. Accordingly, only this complicates the design at least twice. In addition, remember that the part of the tape that runs up and the part that returns are charged differently. Therefore, they will try to attract each other. Therefore, the rollers must be made of a sufficiently large diameter. In ancient times, the accuracy of manufacturing two wooden rollers ... well, you can imagine. The tape on them will jump in jerks and constantly slip. And you can’t slip - the charge constantly leaks.
In the electrophore machine, there is one shaft for two wooden disks. The main task is to balance experienced master even with a knife. No moving parts soft materials. Only two wooden discs with metal heels that don't even touch each other.

3. The storage ball must be made of metal. And the more the better. The ball is hollow, it is necessary to provide a dielectric suspension from the inside, and we also have a design with a rotating shaft inside the sphere.
The manufacture of such an element in antiquity is guaranteed to promise meningitis in blacksmiths. Cast a hollow ball ... This is not even a bell for which you can make a split injection mold! And how much metal will be used for casting and how much will it cost? Here, for sure, the ball will be assembled from sheet metal. The main thing is to make the outer surface as smooth as possible in order to reduce the corona discharges shooting from each ledge. Therefore, the assembly on rivets also promises to be interesting, with lead-filled irregularities a la putty.
And remember - scalability is poor, it is desirable to make the ball bigger, but without fanaticism (in reality it reached almost 4 meters, this does not shine for us, we would at least have a bowler hat).

4. With the accumulation of charge is also a problem. The leaks are very large, so the tape cannot be stopped - as long as the generator is in working condition, it should spin. Did you forget about the wear of the tape? If you assemble an electrophore machine, then the charge will accumulate in the capacitor. There will also be leaks, but much less noticeable. Even for the technology of antiquity. And even if the dielectric in the capacitor is made of ceramics (with glass in ancient Egypt it will be strained).
And at the same time - the capacitance of the capacitors is quite easy to increase by assembling the battery. You can even fill the battery with oil and hide it away from your eyes.
In Van De Graaff, increasing the size of the ball is not efficient, if at all. And the capacitor has nowhere to cling to.
Therefore, Van De Graaff will allow you to receive only high voltage, the current there will be cheap. The discharge of the battery of capacitors can be such that it will easily kill a bull, I am already silent about the magnetization of the compass.

So, Van De Graaff as a generator ... well, it was not for nothing that he was invented for a narrow niche - voltage amplification in laboratory experiments. It was not used anywhere else, and if it was needed where, then the electrophore machine coped with this better. And cheaper. Do you think it's random? 😀

55 Comments on Van Der Graaff Generator

Firstly, the main feature of the VDG is incomprehensible from the article - the charge under a weak voltage is transferred to the middle of the sphere where electric field compensated and redistributed to the surface. Small stress becomes big. There is no such thing in a conventional capacitor - you cannot charge it higher than the available voltage.

>> The manufacture of such an element in antiquity is guaranteed to promise meningitis in blacksmiths. Casting a hollow ball... It's not even a bell for which you can make a split mold! And how much metal will be used for casting and how much will it cost? Here, for sure, the ball will be assembled from sheet metal.

Homemade ones are made by wrapping foil around a wooden or ceramic ball.

>> In Van De Graaff, increasing the size of the ball is not efficient, if at all.

Vice versa.
>> Since a Van de Graaff generator can supply the same small current at almost any level of electrical potential, it is an example of a nearly ideal current source. The maximum achievable potential is approximately equal to the sphere’s radius multiplied by the e-field where corona discharges begin to form within the surrounding gas. For example, a polished spherical electrode 30 cm in diameter immersed in air at STP (which has a breakdown voltage of about 30 kV/cm) could be expected to develop a maximum voltage of about 450 kV.

>> And the capacitor has nowhere to cling to.

Et why? Earth-sphere - everything will be perfectly charged.

>> In ancient times, the accuracy of manufacturing two wooden rollers… well, you can imagine.

Maybe it's enough to remember the steam cylinder into which they put a coin? It was made in the most primitive way - a log that was turned over by a dozen people. And as soon as it became clear that it worked, they made a machine for boring cylinders. Accuracy in fractions of millimeters was quite standard. The calibers of muskets, for example, were maintained with such accuracy. For now, accuracy in the top ten and below is a product of the industrial revolution. But for a tape under tension, this is not necessary.

With VDG, of course, there are more hemorrhoids than with electrophore, but the result ... Hundreds of kilowatts allow you to get effects that amaze even contemporaries.

In general, a ruler for a hitman: a Kelvin dropper - near-zero costs, min result, IOP - a bunch of hemorrhoids and a very cool result, an electrophorus is the golden mean.

The main hemorrhoid is apparently a tape. Impregnate ordinary fabric with dandelion juice, or collect cobwebs (an excellent dielectric and the material itself will amaze the client) 🙂

>> the main feature of the VDG is not clear from the article

Well, I mentioned the multiplier several times, but you can write more explicitly.

>>foiling a wooden or ceramic bowl

Foil in ancient times - only gold with all the consequences (and even then, in ancient Egypt, it is not available).

>>Earth-sphere - everything will be perfectly charged

Very bad decision, immediately limits the possibilities. Yes, and in the very solution of restrictions through the roof.

>> Maybe it's enough to remember the steam cylinder into which they put a coin?

I'm a little off about that.
The cylinder had problems with steel processing. Here are wooden rollers that were sharpened on lathe in the same Babylon without problems. BUT! The rollers should spin, and preferably faster. And this axle on wood will break very easily, as well as issues of lubrication and other things.
I'm not talking about the time of the industrial revolution, but much, much earlier.

>> Kelvin dropper - near-zero costs, min result, IOP - a bunch of hemorrhoids and a very cool result, electrophorus - the golden mean

O! That's what we're talking about! Electrofor is our everything!

Casting a hollow ball... It's not even a bell for which you can make a split mold! And how much metal will be used for casting and how much will it cost? Here, for sure, the ball will be assembled from sheet metal. In doing so, the main thing is to make the outer surface as smooth as possible in order to reduce corona discharges shooting from each ledge. Therefore, the assembly on rivets also promises to be interesting, with lead-filled irregularities a la putty.
And remember - scalability is bad, it is desirable to make the ball bigger, but without fanaticism (in reality it reached almost 4 meters, this does not shine for us, we would at least have a bowler hat).

Let them pour 2 pots. Remove the excess, fasten the resulting. Stylish, youthful, if the fakir is drunk, then the experience will fail.

With a dielectric tape, you have to bathe. Crazy idea - resins are dielectrics. Will satisfy technical requirements tarred fiber?

Is wax also a dielectric? And if you wax?
- The wax will melt. And besides, when passing around the roller, it will crumble (do not have time to soften), which will remain on the roller. Meningitis.
  - This can only be verified empirically, the wax residues that have impregnated the fabric can be more than enough.
    
    But it makes no sense to chase the voltage, you need a current, and for this you need a lot of parallel electrophore machines, and it’s VERY not a fact that it’s the classic Wimshursts. It is necessary to consider the whole class of devices, there are much more technologically advanced designs. It is even possible that banal friction, a lot of glass disks on the shaft and wool will win.

Colleagues, are you kidding?
The ball must be ordered to a coppersmith from the nearest city - the Egyptians perfectly knocked out cauldrons, jugs and helmets from a single piece of copper.
Ribbon of the peleton - plates of fused sulfur, even sealing wax of amber, fastened with bronze rings.
And finally, rollers. Spindles for spindles were made in the Neolithic. Potter's wheel and wheel with a hub - the second millennium BC. What are the problems in making two rollers?
And the first century of our era is Heron of Alexandria with his turbine ball, and from that time it is possible to implement almost any mechanics that was actually built before the first decade of the 19th century.

It is clear that everything can be done. I just pointed out the difference between the creation of an electrophorus and a van de graaf. With such difficulties with coppersmiths, rollers and fabric (it’s strange that you didn’t indicate that some Heron also received rubber: D), then what for, van de graaf gave up?
What's the use of it, if you can make an electrophorus?
- Once again: what are the difficulties with hiring a coppersmith and making commercials? Where did you see them?
  And please indicate where in my comment there is the word "fabric".
  
  About how you are going to balance the disks of an electrophorous machine without the help of a mechanic of the level of Heron of Alexandria (first century AD, Roman Empire), I no longer ask. And from what material will you make them in Egypt, say, in the blessed times of the New Kingdom.
  - You criticize secondary tasks, omitting the main ones.
    I did not say that it is impossible to make rollers or a ball. I said that it would be much more expensive than two electrophore disks.
    And what I said about shafts and tension is also short-lived.
    And taking into account the lack of fabric, this is close to impossible.
    
    And the discs are made of wood and balanced with a knife. That they will not be perfect ... Well, look at the second photo in the article. This mass-produced electrophore has a distance between discs from 2.5 to 7 mm (according to the specification!). That is, no one even tries to balance exactly. And nothing.

And yes, by the way.
You are in vain hoping to magnetize something with the discharge of a high-voltage generator.
The generator is a capacitance, the solenoid is an inductor. A classical oscillatory circuit is formed, in which, during the discharge, damped oscillations will appear, a sinusoid modeled by an inverse exponential. It is good to demagnetize with such an apparatus, but not to demagnetize.
In addition, for magnetization, the time of existence of an external magnetic flux must exceed the relaxation time of the material, and therefore a constant current source is required.

I wanted to write that Kraz is again trying to pull up the sources to get along)))) or better like this:

trying to prove in advance the erroneous, OWN, opinion that one is worse than the other)))) while appealing with extremely poor knowledge about the level ancient technology(honestly, I laugh so rarely and 80% of this laughter is most often over kraz scribbles) ... author burn esche ...

But comrade kiploks overtook me...
Threat kiploks-have my respect
ZYY kraz smoke sources)))

Oh oh comrade...
And Nitsche, that I easily magnetized a magnet from a socket as a child?

I am selling a terrible secret - you need to turn on the fuse in the circuit with the coil around the magnet. Some weaker one. Then put this design into the socket - when it reaches the maximum, the fuse will immediately burn out and the magnet will remain magnetized.

In ancient times, there are no fuses, you need to replace it with an instant touch, this is not difficult even for Sumer.
- As a child, I charged a capacitor from an outlet, and what does this prove?
  You draw what happens on the magnetization curve in the case of a network alternating current low voltage and constant amplitude, and what - when a high-voltage capacitor is discharged to an inductive load?
  - Well, wonderful, draw me a discharge in the oscillatory circuit, when the circuit opens after the first half of the period, yeah. 😀
    - You have a capacitor of 1000 picofarads maximum. To break the current before it goes "to the minus" you need to have time to do it faster than half the period of the oscillation of the circuit. To get a frequency of 50 Hz you need (according to my calculations) a solenoid with an inductance of about 1000 Henry. You do not have an active key or diode and will not appear soon, the fuse at voltages of 10 kV turns into an arc gap and there is no help for you - ionization in the arc trace disappears too slowly even for a frequency of 50 Hz.
      You simply will not be able to turn off the current before it runs out on its own.
      
      If you don't believe me, the Internet is full of projects of electrophoric machines made from a piece of plexiglass and shoe lace. Check it out yourself.
      - Why did you choose exactly 1000 picofarads? Who will stop me from stuffing the whole room with air conditioners? Here the main limitation of capacity is money. Yes, glass ones are no longer suitable, you need to look for cheaper ones. We will look for .. (by the way, really interesting)
        
        And your calculations are wrong. Who prevents to make a mechanical circuit breaker? Which will short out for a split second? For example, a three-meter lever with a contact at the end, flying next to another contact, between which an arc flashes?
        
        No, seriously - you can think of such solutions as a bucket and a small cart.
        
        On the one hand, a thousand henries is not as scary as 1000 farads, the inductance still grows as the square of the number of turns. A few kilometers of wire will allow us to make such a solenoid. At 50 hertz, adding tens of kΩ of resistance to such a circuit will reduce the quality factor to such an extent that opening is not needed at all, and the current due to voltages will still be measured in amperes.
        
        But of course, given that this chthonic construction of a capacitor, a megasolenoid and an electrophore (plus, perhaps, a switch with a response speed of hundredths of a second) is replaced by a voltaic column - even if we make it from copper and gold, it will turn out cheaper. Electrostatics is only good for killing minds.
        
        Eh, I just want to take and build such an electrophorus! Calculate the coils - and magnetize the needles for testing.
        
        And about cheap electroplating - no need. Simply because the galvanic cell is a consumable element. A properly built electrophore will spin for decades.
        
        Consumable? Ten times more needles than he weighs, he somehow magnetizes. Or a hundred? Nothing less.
        
        What about the number of needles?
        With electroplating enough hemorrhoids drain-fill electrolyte. And there are all sorts of measurements of density and in general the quality of the electrolyte, the gases released, and much, much more. Because chemistry, which at that time will not give a guaranteed result.
        
        Here, after all, it is necessary not to magnetize a ton of needles at a time, but from time to time.
        
        And the electrophorus is pure physics, there are not so many parameters that they constantly want to scatter.
        Well, the electrophorus in the copper age - that's it, iron is needed only for a compass needle.
        
        Electroplating is necessary if you need to galvanize something.
        But if, in addition to needles, you need effects in the temple, then the electrophorus wins. Or even van de graaff, his discharges are branchier. 🙂
        It will work out especially well if voltage is applied from the electrophore to the van de graaf (in fact, the van de graaff was invented as a multiplier).
        
        Start by calculating how much energy it takes to magnetize the needle and compare it to how much an electrostatic generator produces.
        
        1000 picofarads is the standard capacity of a Leyden jar.
        Where will the money for the capacitor shed come from?
        Electrostatic generators are designed to generate high voltage. High voltage - glass capacitors, any other insulator material will either not withstand the voltage, or will cost as much as a knight's castle.
        Mechanical disconnect with opening speed less than 50 milliseconds and voltage >1 kV? With a current of more than an ampere and extinguishing the arc? I want to see it.
        Mechanical solutions over the past century have indeed been offered "a cart and a small cart." But none of them worked...
        
        I specifically stipulated that you need not a Leiden jar, but namely air conditioners and glass ones (although you need to look for options, I don’t know what is there with ceramics).
        At the same time - do not care that the van de graaff, that the electrophorus - capacitors are needed. Without them, they are just toys with sparks.
        
        And you can also tinker with mechanical opening - here the question is in selecting the parameters of the oscillatory circuit so that its frequency is as low as possible, then the circuit breaker can turn into a knife switch.
        And there were mechanical solutions for other cases, compasses were successfully made in more industrial ways.
        
        What about mica capacitors? They mined it in the mountains.
        
        Yes, a possible option.
        You need to look at the electrical qualities, where and when and how much was mined.
        
        They write this:
        
        “High insulating qualities (high leakage resistance, low losses at high frequency) make it possible to use mica capacitors up to very high frequencies in almost any radio circuit circuit. The insulation leakage resistance of mica capacitors has a value of about 10 ^ 10 Ohm, i.e., an order of magnitude higher than the leakage resistance of paper capacitors, but in terms of geometric dimensions, mica capacitors are much larger than paper capacitors with the same capacitances.
        The facings consist of lead-tin foil or silver.
        
        As for deposits: large deposits muscovite - on the Kola, in Siberia, India, Brazil, Canada and the USA.
        
        “In the north-west of the European part of the USSR, there was an ancient mica industry. The deposits were known as early as the 15th century.”
        
        In general, mica interesting stuff from the point of view of the hitter.
        
        “The most valuable sheet mica is used mainly in the electrical industry: for insulators, capacitors, rheostats, telephones, magnetos, electric lamps, kerosene, mica glasses and other purposes. Depending on the size of the plates, the degree of their transparency and uniformity of color, several varieties of sheet mica are distinguished.
        
        Mica powder (scrap), obtained by grinding waste, is used in the manufacture of fire-resistant building materials(roofing felt), wallpaper, writing paper, refractory paints, various ceramic products, car tires, for explosives (as an adsorbent), lubricants etc."
        
        And, and was used to fasten the fittings of electronic lamps.

The most common foil in "pre-aluminum" times is TIN. There are no problems with her. You can also stupidly “paint” a wooden ball with graphite or metal powder (bronze). Yes, high resistance. And what? The currents are meagre.

Modern "ribbons" in VDG generators are made of METAL links with dielectric separators.

By the way, I tried paper tape. For a "desktop" device - it goes to its full height.

"Wear" rollers? Well, if you make an aggregate several meters high, maybe, but if a small one falls apart, it’s not from “wear and tear”. In any case, I don’t remember that I had something “worn out” in wooden spools of thread. Construction nails served as axes 🙂
Furthermore. The voltage that a device can generate depends only on the linear size of the generator.
A meter-long wooden disk or a meter-long “conveyor”, which is lighter? And where will the axle load be less?
But I'll point it out again. Mechanical problems will only occur with truly large units.

Electrophore machine - two disks with a diameter of 1 meter is equivalent to a VDG 1 meter high and with two rollers a few centimeters in diameter.
It is not necessary to argue that it is easier to make a meter disk than a 5 cm roller.

At VDG trouble. Since the current (rate of charge transfer) is proportional to the linear speed of movement of the elements, the VDG needs high revolutions. It's true.

And finally, if you really want to use the EDC as a "multiplier", then put two EDCs side by side. Only this is not a “multiplier” 🙂

So far, I can see from your descriptions that van de graaff in ancient times is even more difficult to make than I figured.
And I did not see what you will make the tape from. Do not offer metal links, they will either not do it in any way, or they will do it for the money for which you can make one hundred or twenty electrophores. These are those with meter discs. And, by the way, if the tape is made of links, then what will the dielectric separators be made of?

And the wear of the rollers (read carefully) is the wear on their shaft, they will simply hang out and the tape will slip.

Paper is great. It remains only to build paper production. Or would you dare to make a ribbon out of papyrus? 😀

No, van de graph has its own plus - more tension.
Do we really need this plus?
- The soul of the poet could not bear .... Decided to intervene... It's just a shame to watch how the pripons are sucked out of .... well, let there be a finger))))
  Kraz, if from the very beginning you decided that one is better than the other, then God will be your judge ....
  
  1 for the manufacture of a sphere - we look at chasing (this is if historical methods) or, as a variant of hitting, drawing on a lathe ...
  2 believe me, dielectrics are very common))) skin bone ... wood ... and so on
  3 in terms of roller wear, the simplest device for changing the tension and an oil seal with lard)))) the same mills have been working for years))), no one has canceled other lubricants ...
  - I just didn’t understand which of this is easier than an electrophorus. 😀
    
    Once again, for those who do not read, the article is not about the fact that it is impossible to do this.
    An article that it will be much more complicated and more expensive than an electrophore. And much more unreliable.
    And that's exactly what this article is about.
    
    Although if you are a fan of “why is it simple, if it can be difficult” and you grow potatoes in flowerpots, and ride a scooter strictly along the curbs to work, then I am powerless. 😀
    
    P.S. I'm afraid that skin-bone-wood is not suitable for such stresses. And the only advantage of a van de graaf over an electrophore is an even higher voltage.
    - I don't understand, I'm sorry I'm like this))))
      What is the difficulty???? What is the cost??? The simpler the electrophorus (especially large) ???
      
      PS Well, I’m just omitting the very idea of the uselessness of all this)))), forgive me, I still think that a hitman in antiquity and the Middle Ages is primarily a loner, he should not attract undue attention ... this will end badly for him))) ) therefore, the technologies of the hit (in the head / records) should be designed for the implementation of 1 person (if the hit is 1) ...
      - But what to use for is a question, and the answer here is exclusively in the character of the hitman himself. He has acting skills - you can think about creating a sect, otherwise - only magnets.

Hahahaha! So at high speeds there will be a plug, the complexity of the bearings and the overdrive transmission will kill all the benefits.

But I still think that the electrophore machine is also too complicated, a lot of fine mechanics, it does not scale well. Armstrong's electrostatic steam engine (from water-cooled nozzles blows a mixture of steam with drops resulting from its cooling and hits them at a plate at a distance), for example, can be much more powerful and efficient, and an engine is not needed. Not necessary high pressure, you can rivet a boiler from copper sheets. And very high power compared to mechanical designs.

If you make an “industrial” generator, then yes, there are bearings and a tension system and in general ... But if you show a “ritual” sample or show ...
I had a generator paper tube, two nails, two spools of thread and paper tape.
Moreover, one nail was motionless and a coil was spinning on it, the other was a movable axis and was spinning right into a hole in the paper 🙂 In a few hours of total work, nothing fell apart.

By the way, Ros, thanks for the thought. Leather belt - quite in the vein. R. Wood in the “generator” had leather belts.
- By the way, the DC motor is made of varnished wire. WIRE ONLY. The secret is in the partial stripping of insulation.
  - But with wire varnishing - this is a topic.
    This is definitely a hit technology and it will need to be painted.

Addition. I didn't have a metal ball. And to wrap the light bulb with foil, I blunted (it was 10-11 years old), so the upper electrode simply stuck out with a wire sideways and down. From it, during the operation of the generator, the discharge constantly rustled towards the lower electrode.

And why all the same van de Graaff? or electric fork?
After all, there are several more ways to get a high charge. for example, there is a steam engine that produces a static charge and is not weak more than a million volts. More precisely, it is just a boiler with escaping steam. It is possible to receive a charge from the atmosphere.

about Conders and Leyden jars… well, what nonsense, guys. you say only gold foil is good? but you can't roll sheets out of tin. But what about lead? don't be stupid guys!
there is a description of the Ark of the Covenant in the Bible and in the Jewish Torah, and something that happened to it. so it turned out to be a typical capacitor. and easily charged in the dry climate of Israel, literally to a lethal charge. It was covered with silk. and the walls were upholstered with gold plates. It's all wood. and it worked.
'bout over expensive glass. Damn, don't make fun of my slippers. Do you need Venetian glass? You can make the simplest glass yourself for that electrical purpose. sand and soda. It is true that it dissolves easily with water, but you can use it for vessels with water and for insulators.

Ahh, I recognize the epic character from the ateism.ru forum several years ago. There was (or still is - I don’t know) such a character - he kept moving about the ark-capacitor and about the priestly vestments, stitched with gold thread, like suits for working under high voltage. Freaks are freaks.

By the way, it is easy and more reliable to replace the Nubians with a simple donkey and an overseer boy.
Leyden jars can be made from ordinary clay pots. and articles made of fired clay will make excellent insulators.
Wire, once you need it, is difficult to do, but who said that you need a round one? roll out long strips from the same lead and that's it!
🙂

I was not on atheism, do not attribute other people's merits to me.
🙂
I am not saying that the ark of the covenant was specially made as a conder. It just turned out that way. Wooden walls upholstered on both sides with metal (in that case, gold) form a capacitor, voluntarily or involuntarily. I mean, in the dry climate of Egypt, you can do this. Somewhere above there was a mention of some period of the kingdom of Egypt.
As for priestly vestments… I have no idea where they get their legs from. but in the Indian treatise about vimana and others. there is mention of a special treatment for pilot suits rukma vimana (or something like that). I also thought that it resembles the processing of clothing for chemical protection. There was such an item in the "civil defense". how to prepare your own clothes in case of a chemical attack. That's when I read about processing by Indian translators. then I thought it was something like "linor" antistatic agent. Which suggests that the device used a very high voltage. Maybe it was an analogue of the "lifter"? There are a bunch of videos on youtube about them.

I remind you that in order for the ark to work as a capacitor, firstly, the plates must not be closed, and secondly, both must be brought out. It is somehow doubtful to me that both points will be inadvertently observed, because they are almost mutually exclusive.

Let me guess. Have you watched Future Memories recently?

Well, it's very similar. Freaks in general are all similar to each other.

as far as I understand. covers did not close. and the conclusions were out. The fact is that a group of "mythbusters" was engaged in this matter. built a copy according to the description in the Torah. and got positive result- the ark really turned out to be a conder. Which confirms those ancient records that a porter was killed and several others were hit.

Van de Graaff generator capable of delivering electrostatic potentials of hundreds of thousands of volts. Such installations are available in many laboratories and polytechnical museums, where they are used in a wide variety of experiments related to electricity. True, they use generators two human heights high. We will try to build a compact desktop installation.

The generator is named after the Dutch physicist R. J. Van de Graaff, who in 1931 designed it for his experiments on electrostatics. Since that time, installations throwing sparks can be found even in the school physics classroom, and they are sometimes called electrophore machines. We will try to make with our own hands approximately such a generator, as Van de Graaff himself conceived it.

To design a Van de Graaff generator, you will need:

empty metal soda can;
a small carnation;
ring gum with a width of about 0.5 cm and a diameter of 8 - 10 cm;
glass electric fuse with dimensions 5 × 20 mm;
DC motor (for example, from a toy);
clip "crocodile";
battery holder;
styrofoam cup or paper cup;
adhesive thermal gun or a tube of glue for plastic;
two pieces of copper electrical wire;
two pieces of 3/4-inch plumbing pipe PVC;
3/4" PVC sleeve;
T-piece 3/4" PVC plumbing tee;
electrical tape and wooden stand.

It may seem that the installation is complicated, but if you look at the illustrations, you will see that it can be mounted in just one evening. The main thing is to stock up all the necessary details.

Generator installation

Installation start with wooden base. Glue a 5 - 7 cm piece to it plastic pipe 3/4 inch diameter. Your generator will be mounted on this foundation in such a way that, if necessary, it can be easily removed if, for example, it is necessary to replace a rubber band in it or make changes to the design.

An electric motor is inserted into one of the knees of the plumbing tee. Since the motor, as a rule, is of small diameter, it must be wrapped with paper or electrical tape so that the body enters the pipe with some effort. Pull a piece of plastic tube of the appropriate diameter onto the motor shaft.

Next, drill a small hole in the side of the T-tube. Through it, insert the end of the stranded wire, “disarranged” in the form of a brush or brush, in such a way that, placing it near rubber band, it was possible to remove an electrostatic charge from it.

You can secure the wire in place with tape or electrical tape. Throw the rubber band at the bottom of the pulley, and pull the rest up, as shown in the illustration.

Next, cut a 5- to 7-centimeter-long cylinder from the 3/4-inch plumbing pipe. It will need to be secured to the top of the T-socket as shown in the picture. Pull the elastic all the way to the top and secure with a nail.

In this case, it must be borne in mind that the length of the pipe must be such that the elastic band is not stretched too much. Otherwise, due to increased friction, the engine will work with excessive load.

Cut off the bottom of a 1.5 - 2 cm high styrofoam cup, turn it upside down and cut a hole in the bottom so that it fits snugly on a 3/4-inch pipe.

Now drill three holes in the top of the coupler. Two of these holes should be diametrically opposed to each other so that a small nail can pass through them, which will act as a bridge for the elastic. The third hole is located between the other two in such a way that the wire brush-brush threaded into it, like the lower brush, almost touches the elastic band when stretched.

The brush is inserted into the sleeve, and the sleeve itself is put on a 3/4-inch pipe, above the "collar" of the cup. The elastic is tucked into the sleeve and held in place with a stud, as before. By the way, the individual wires of the "brush" must be twisted almost along the entire length between each other so that the individual wires do not fall apart.

Now it remains to put the glass tube in place. The easiest way is to take it from an electrical fuse, which are used in radio devices. Gently heat the metal cap on one end of the fuse with a soldering iron and remove it from the tube with pliers. Do the same with the other cap.

Then pull the end of the nail out of one hole in the sleeve and put a glass tube on it so that the elastic is on the tube. Re-insert the nail into the second hole.

Glue the Styrofoam "collar" to the pipe. It is best to do this with a heat gun, as the glue hardens quickly and does not dissolve the plastic.

But, in principle, the same can be done with another suitable adhesive for plastic.

You are now ready to install the aluminum can. It is good for high voltage because it has rounded edges which minimizes corona. All that remains is sharp knife carefully cut out the top cover, smooth the cut edges, for example, with a screwdriver and, turning the jar upside down, put it on the polystyrene collar, passing the free end of the upper wire "brush" inside.

The last step is to connect the motor to the battery with wires. In this case, the supply voltage must correspond to that for which the electric motor you have taken is designed.

If the brushes at the top and bottom of the jar are set correctly—very close to but not touching the elastic band—you should feel a slight electrical sting as soon as you bring your finger close to the aluminum can.

Starting and configuring the Van de Graaff generator

If you have not found signs of high electrostatic voltage with the engine running (no sparks, the bank does not attract paper strips), then you will have to start setting up the generator.

First, try a different type of gum. Some types of rubber have a certain conductivity, and therefore cannot give a high potential.

Make sure all installation parts are clean. Dirt and grease can also make your installation inoperable.

Check if the top brush is firmly in contact with the metal of the can. Some jars have a plastic coating on the inside. Then it is better to take another jar.

Check for sharp ends that extend beyond the installation. They can become a source of corona discharge, and the voltage will not accumulate.

Make sure the brushes do not touch the rubber band itself. There should be some gap between them.

Van de Graaff generator circuit: 1 - electric motor shaft; 2 - glass tube; 3 - carnation; 4 - wire brush; 5 - sphere; 6 - gum; 7 - wire brush.

Check the correctness of the entire installation by comparing what we have done with circuit diagram installation.

After the generator is set up, consult with a physics teacher what interesting experiments can be done using the generator you made. For example, if you hang a bunch of paper strips on an aluminum can with the generator turned off, then as the voltage increases, they form a kind of exotic "bouquet".

Or you can use the Van de Graaff generator to try to get electrets - eternal sources of electrical voltage, which are used, for example, in microscopes.

This is a high voltage generator, its mechanism of operation is based on the electrification of a moving dielectric tape. It was first created in 1929 in the USA by physicist Robert Van de Graaf and gave a potential difference of up to 80 KV. In 1931, he also developed a device that generates 1 million, and two years later - 7 million volts.

It is known that during friction different materials each other you can get an electric charge, which attracts all sorts of small pieces of paper, dust and even deflect a stream of water. For example, we use PVC sewer pipe and sock, works no worse than the famous ebonite stick. Any substance consists of positively charged atomic nuclei and negatively charged electrons that revolve around them. Usually in a substance, positive and negative charges are equal, so the total zero, such a body is not charged. But when the sock touches the pipe, the electrons move from the sock to it, because the electrons are better attracted to its molecules.

Friction is a way to bring as many molecules into contact as possible, so during the experiment it is better to press down on the toe with more force. But not everyone realizes that in a simple way a voltage of 1000 V is reached; to verify this, it is recommended to do the experiment in absolute darkness, for example, by locking yourself in a room without windows. And observe flashes of discharges that occur when the sock is rubbed against the pipe.

The Van de Graaff generator also receives a charge due to the contact of two materials with each other, but it can receive much more voltage. When arranged, it is quite simple. An engine is fixed at the bottom of the generator, it is needed to rotate a special tape, something needs to be fixed on the engine axis, which, upon contact, charges the tape. We tried a whole bunch of materials to put on the axle, as well as several options for tapes. Martens' medical bandage worked best as a tape, and as a result, pieces of the same PVC pipe were put on the axis, which attracts electrons well, being negatively charged. And the positively charged tape, rotating, carries its charge up, and it accumulates on the metal ball more and more. If you want the ball to become not a plus, but a minus, just stick your fingers into the pipe, the skin gives off electrons during friction. The voltage on the ball accumulates really high, judging by the size of the penetrating lightning, 100,000 V is accumulated. Cool generators created using Van de Graaff technology can generate millions of volts and are used in physics to accelerate particles to high energies.

Why does the tape always only bring charge to the ball, and never carry it away? To answer the question, you need to understand one important property of conductors, because the ball, unlike the tape, is specially made of metal, a well-conductive material. Explanation for the layman, savvy dudes themselves will read about the Gauss theorem and screening.

Suppose there is a piece of metal, and a charge somehow got inside it, let it be a bunch of negative electrons, however, if it is metal, then not even a fraction of a second will pass, as it will not be there anymore, because it is a bunch of electrons, they are all different repel each other. Quickly, all the excess charge will be smeared on the outer wall of the metal in a very, very thin layer, i.e. always accumulates on the outer surface of the conductors. Therefore, the tape cannot take a charge from the ball, it simply does not exist inside. This is the basic principle of the Van de Graaff inventor's generator. The whole trick is that we bring the tape from the inside of the ball, and not from the outside.

The ball was made from two salad bowls bought from Ikea. Inside is a bicycle sleeve, on which the tape is held, freely rotating. The charge from the tape to the ball gets either through the sleeve or with the help of an additional wire brought as close as possible to the tape. At the end it is divided into many small sharp conductors. The fact is that the charge drains much better through the air on the tip. The ladle into which lightning strikes is grounded through the body of a homemade generator.

The Van de Graaff generator is actively used in various laboratories, and it can also be found in polytechnic museums and all those places where experiments with electricity are carried out. This device is capable of generating an electrostatic current with a power of several thousand volts.
This name was given to the generator in honor of the Dutch physicist R. J. Van de Graaff, who created this interesting machine in 1931. Today, such installations are actively demonstrated at school in physics lessons, they are called electrophore machines. This article will discuss how you can make a small copy of such a generator from improvised materials with your own hands.

Materials and tools for homemade:

- a small nail;
- empty aluminum cans from drinks;
- an elastic band (about 0.5 cm wide and 8-10 cm in diameter);
- little electric motor(from a toy, hair dryer, etc.);
- glass fuse (size 5x20 mm);
- "crocodile" (clip);
- a clamp for the battery;
- a paper cup or a cup made of polystyrene foam;
- a tube of glue for plastic or a hot glue gun;
- two pieces of copper wire;
- two pieces of plumbing PVC pipes 3/4 inch diameter;
- 3/4 inch PVC sleeve;
- plumbing tee 3/4 inch;
- wooden stand and isolnet.

Generator assembly process:

Step one. Assembling the generator housing
The body of the generator consists of PVC pipes, a wooden stand is used as a base. First you need to take the base and glue a piece of plastic pipe 5-7 cm long to it (the diameter of the pipes used is 3/4 inch). Next, a PVC plumbing tee is put on this pipe. Thanks to this design, the device can be easily disassembled if you need to replace the rubber band or carry out any other work inside.

Now you can install the engine, it is inserted into the hole of the tee and is located horizontally. If it turns out that the diameter of the motor is too small, it must be wrapped with electrical tape, it must enter the body of the tee with some effort. In order for the motor shaft to interact with the rubber band, you need to put a piece of tube on it. An ampoule of a helium pen or, best of all, a soft rubber cambric from a wire is suitable, this will provide excellent grip with the tape.

After installing the engine, you need to take a drill and drill a small hole opposite the engine shaft. Then you need to insert a piece of stranded wire into it, disheveled at the end. It will remove an electric charge from the tape. The wire can be secured with hot glue or tape. Now it remains only to put an elastic band on the motor shaft and pull its other end through the top. After that, you can proceed to the next step.

Step two. Making the second axis
Now gotta get another one a piece of pvc pipes and cut off a piece of 5-7 centimeters from it, it will be inserted into the upper part of the tee. The length of this piece of pipe must be such that the rubber band is not too tight, otherwise it will not be able to rotate. But the tape should not sag too much. After a certain length has been reached, the elastic can be temporarily fixed at the top with a nail.

Next, you need to take a polystyrene cup and make a 3/4 inch hole in its bottom. The glass is put on the tube with the bottom up, the tube should go into it tightly. It is needed in order to final stage install aluminum can.

After installing the cup in the upper part of the pipe, you need to drill three holes. Two are needed in order to insert the second shaft, and the third to establish a contact. A nail is used as a shaft, on which a piece of glass tube is put on. When rotating, it has the smallest friction. The author made such a tube from a glass fuse. To remove the metal caps, they must first be heated with a soldering iron, and then carefully pulled off with pliers.

Well, then it remains to connect the second brush, as in the first case, you need to straighten the bristles on the wire and make sure that it is at a minimum distance from the tape, but does not touch it. The wire is fixed with tape or glue.

Again, to make the system easier to disassemble, you can make the top part removable using a plastic pipe sleeve. How to do this, you can see in the photo.

Step three. Final build process
At this stage, the structure will be fully assembled. First you need to fix the cup, for this you can use hot glue or special glue for plastic.

After that, you can install an aluminum can, for this, in its upper part, you need to cut a hole that is suitable in diameter for the cup. The jar should fit snugly on it.

Thanks to the rounded edges, such a jar is excellent for high voltage applications, as "corona discharge" is minimized. You also need to remember to pass the free end of the wire from the top brush inside the can.

Well, now it remains only to connect the system to a power source, it can be either a battery or any other power source of suitable voltage. If the design is assembled correctly, pieces of paper should be attracted to the jar, and the current discharge is felt to the touch as a slight tingling. If these phenomena are not observed, then perhaps a mistake has been made somewhere. You can try using a different rubber band and check the contact gap between it.

Accelerators of charged particles—electrons, protons, and ions—are used in various fields of science and technology. Such accelerators can be built on different principles. Including on electrostatic principle. One type of generator built on this principle is the Van de Graaff generator. This device, which was invented in 1929 by University of Massachusetts professor Van de Graaff, used the principle of creating an ultra-high voltage field by electrifying a dielectric tape that moves with the help of a motor.

Design and principle of operation

The design of the generator is vertical and horizontal. The most common is the vertical installation.
This generator includes:

an endless dielectric rubber or silk tape moving at a speed of 20-40 m / s on 2 rotating pulleys;
2 pulleys. The lower pulley is made of metal and is rotated by an electric motor, while the upper pulley is made of a dielectric, such as acrylic glass;
a hollow metal electrode in the form of a hemisphere, inside of which there is an upper pulley. This electrode is mounted on an insulator;
high voltage source.

The bottom pulley is grounded. A high voltage is applied to the electrode located near this pulley. At a short distance from the upper and lower pulleys, electrodes are installed, made in the form of a brush or comb. The top electrode is connected to a hollow hemisphere.

The principle of operation of the device

Under the influence of high voltage in the air layer located between the lower brush electrode and the lower pulley, positively charged ions are formed. These ions are attracted to the metal pulley, deposited on the dielectric tape and transported to the hollow hemispherical electrode. With the help of the upper brush electrode, these ions are removed from the tape and fall on the surface of the spherical electrode. Over time, there is an accumulation of charge and an increase in the potential of this electrode relative to the ground.

The maximum value of the resulting voltage is determined by the voltage of the discharge that occurs around the spherical electrode as a result of ionization of the air surrounding the electrode. As the diameter of the sphere increases, this stress increases.

To increase it in installations with a relatively small sphere, the device is placed in a hermetic case, which is filled under a pressure of 20 atmospheres with gases with high electrical strength. These gases include nitrogen, freon and other gases. Such an enclosure, made of insulating materials, also serves to ensure the safety of people.

tandem generator

The tandem generator consists of 2 stages. This generator creates negative ions, which fly towards the electrode under a high positive potential, located in the middle of the vessel filled with gas. Passing through the channel inside the electrode, negative ions with an energy of 10 MeV give up their electrons and turn into positive ions. Further, the beam of these positive electrons moves towards the electrode having zero potential. Thus, it is possible to obtain a beam of protons with twice the energy.

Usage

Van de Graaff generators are often used in atomic research and medicine.

In the first case, they are used to carry out nuclear reactions and to introduce particles into accelerators. There are such installations in most nuclear laboratories, in which researchers deal with particles of low and medium energies.
In such accelerators, under the influence of the voltage generated by the generator, particle beams are formed and accelerated.

In the second case, generators are used for radiation therapy and research. In this case, the particle beams hit the target and create hard radiation.

In addition, such generators can be used as teaching aids to demonstrate the phenomena of electrostatics, as well as to study lightning discharges and lightning strikes.

Specifications

The 1st generator of this type generated a voltage of 80 kV. Later, the inventor received voltages of 1 MV and 7 MV. The voltage of the primary source was 50 kV.

Modern installations make it possible to obtain with the help of this generator a voltage of 20 million volts. For this, tandem installations are used. In this case, the current in the beams can reach several mA, and the particle energy can reach 40–50 MeV.

To obtain particles with higher energy, more powerful installations are used - cyclotrons, colliders.

Most powerful generator Van de Graaff was used in the English laboratory Daresbury, in which nuclear experiments were carried out from 1983 to 1993. A tandem generator was used in the installation, developing a voltage of 20 MV. This generator was located in a building 70 m high. The most important discovery made using this installation was the discovery of superdeformed nuclei.

Before the war, a large generator of this type was also built in the Soviet Union. Metal balls with a diameter of 5 m were installed on 2 porcelain insulators. The voltage between the balls reached 15 MV. During the discharge, lightning appeared with dimensions of 15 m. At the same time, the charge time reached 10 minutes, and the average power of the installation was less than 100 watts.

Generators for experiments and education

Van de Graaff generators can be used for experiments in the field of physics and electrostatics. However, a large number of generators are commercially available. Also on the Internet there are many different schemes and designs for self-manufacturing generator.

An example of such a device is a generator manufactured by the German company 3B Scientific GmbH. The price of such a device is 104076 rubles.

The main characteristics of the device:

the generated voltage is about 100 kV;
short circuit current-15 uA;
motor power supply from the alternating current network;
power consumption -13 VA;
dimensions -240x120x620 mm;
ball dimensions - diameter 90 mm, height 420 mm;
generator weight -5.8 kg.

When working with this device, you must comply with a number of safety requirements:

This device may be dangerous for people who have a pacemaker implanted in close proximity to the device.
Computers and others electronic devices it may cause RF interference.
Do not use the device in damp rooms.
Do not touch the circuits of the device.
You can only turn on the device in a mains socket with grounding.
When replacing a fuse, be sure to unplug the appliance from the mains.

Preparing and turning on the device:

Before turning on the generator, remove the sphere by lifting it up.
Clean the surface of the pulleys. If necessary, wash them and dry them with a hair dryer.
Install the belt into the pulleys.
Put the sphere in place.
Ground the metal plate and electrode.
Start the engine and select the desired speed.
To check the charge by obtaining a spark, slowly move the tape towards the metal sphere.
In case of humidity, dry the device with a hair dryer.

Advantages and disadvantages

Dignity Van de Graaff generators are that with their help it is possible to obtain beams of charged particles, which have the following properties:

continuity;
high intensity;
excellent energy stability. This characteristic of the beam reaches a value of 0.01%;
small divergence (less than a thousandth of a radian).

Disadvantages of generators:

restrictions on the magnitude of the resulting stresses and particle energy;
increased requirements for the breakdown voltage of the column and strip;
difficulties in measuring ultrahigh voltages;
the presence of rotating parts that reduce the reliability of the device.

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