Nuclear energy

[Read-Only]

The easiest way to produce a large number of electrons in a stream is with an electron gun. These are found in the old style CRT television sets. The electrons are produced by heating an element to the point that loosely held electrons are emited the electron beam is acclerated and focused in an electiric field.

Electron Gun.

DO NOT try and investigate an electron gun from a television!!

Even after the television has be unplugged for a considerable amount of time there are capacitors in the television that could discharge and KILL YOU.

And in the old CRT-type set it's actually the CRT itself (picture tube) that presents the greatest danger of electrical shock. The "boosted boost" power supply that furnishes the charge to to the CRT will self-discharge fairly rapidly BUT the CRT is actually a large capacitor and has no built-in discharge path. It has to be done manually. And unless it is, the CRT remains dangerous for quite a LONG time.

[jaiii]

Thanks.I knew electron gun.But I thought about : it is possible use electrons from second
ionisation in thermo elektric generator.

By.

[river]

I haven't looked, so I don't know. But, I would strongly suspect that there has never been more than one pellet fused. And that as soon as fusion began, the reaction was uncontrolled and died.

it is only one pellet ,( hydrogen atoms ) and it is round , the lab is in California , National Ignition Facility ( a PBS program Hunting the Elements series )

You have to be able to contain the fusion reaction, and there is no material which can accomplish this.

then why do it ? if there is no material that could handle the reaction

With laser fusion, (as I understand it), the lasers are aimed so that they provide equal containment force, but as soon as the fusion reaction begins, it fizzles due to containment failure.

wouldn't the mass used though need a critical mass so to speak , I would think so

[KilljoyKlown]

then why do it ? if there is no material that could handle the reaction

Don't they normally use magnetic fields to contain hot plasmas? So what's really being said is we can't create magnetic fields of sufficient strength to contain the reaction. But we are still improving our ability to generate strong magnetic fields. Anyway they are still learning and we are making progress even if it seems a bit slow.

[river]

Don't they normally use magnetic fields to contain hot plasmas? So what's really being said is we can't create magnetic fields of sufficient strength to contain the reaction. But we are still improving our ability to generate strong magnetic fields. Anyway they are still learning and we are making progress even if it seems a bit slow.

but not only magnetic fields but a mass large enough to sustain it as well , a critical mass , much larger than the hydrogen pellet , and perhaps a constant flow of hydrogen

[KilljoyKlown]

but not only magnetic fields but a mass large enough to sustain it as well , a critical mass , much larger than the hydrogen pellet , and perhaps a constant flow of hydrogen

I thought the idea was to fuse one pellet after another in a regular cycle and the faster they can do that the more energy they will produce.

[river]

“ Originally Posted by river
but not only magnetic fields but a mass large enough to sustain it as well , a critical mass , much larger than the hydrogen pellet , and perhaps a constant flow of hydrogen

I thought the idea was to fuse one pellet after another in a regular cycle and the faster they can do that the more energy they will produce.

it doesn't seem so , at least there is no indication or talk of one pellet after another

[jaiii]

When I well understand the main problem of the fusion is that they spontaneously expand and it is impossible to control.

So I was wondering if the atoms added to the mixture, for example, Carbon atoms or Xenon.
What would have happened.
Whether it be someone try?

By.

[Billy T]

... So I was wondering if the atoms added to the mixture, for example, Carbon atoms or Xenon. What would have happened.
...

The plasma would not get hot enough for fusion, even of D&T, due to fact these higher atomic number elements would not be fully ionized. I.e. they would be a very strong radiation energy drain. In fact fusion researchers go to great efforts to keep the higher atomic number atoms blasted off the vacuum chamber wall out of the plasma they are trying to heat. They do this by having some of the near wall magnetic field lined bend out of the main reaction volume - that field structure is called a "diverter." I.e. as soon as a neutral wall atom is even one stage ionized it is gyrates around the local field lines but can flow freely along them out of the reaction area. Thus the "quenching" of the plasma is avoided.

Man can already make magnetic fields strong enough to confine economically useful thermonuclear plasma because the pressure they must contain, at fusion temperatures, is linear in plasma density. It does mean that the energy density in a fusion reactor is quite low - as I recall, signifcantly less than in a common steam turbine´s inlet steam. Energy density of the plasma is only one factor determining the power level - the reaction rate is more important.

Magnetic field strength is not the problem. Avoiding instabilities is.- The hot high pressure plasma "knows" many dozens of ways to slip between the field lines and escape.

[jaiii]

Thank you for your reply. I asked this question several times, but until you've answered it.

Thank you.

Good-bye.