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Author Topic: Fusion  (Read 2962 times)

Offline Zephyr

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Fusion
« on: 23/11/2007 18:49:33 »
Hey yo people, first post, but I'm going to be a regular poster from now on. I'm only doing GCSE sciences, but I'm bored because I've always read ahead and have been told recently I could do my A levels if that was allowed, and do well. But thats not bragging, just a little background information so my theory could be believed. I'm not some rambling teen with an idea.

  So I read a huge electric charge has a field of it's own the other day. Something to do with the huge negative force of the electrons in the current, and I reckon a current of about a thousand amps would suffice if you have the equipment. Fusion gets it's heat from an electrical current, correct? To turn the gases to plasma containing light nuclei such as tritium and the like. Well, I've notice they always run the current in from the side, and then have to waste huge amounts of energy with the electromagnets to keep it off the sides and keep fusion going.

  Well, in regards to this huge current, how about running it up to power the fusion from the centre? That way the force of attraction from the center will pull the positive neutrons in an orbit around it and create such huge heat that fusion will happen self-sustainably.

  Any ideas on this? I know I can't get a scientist to take my ideas seriously as I'm 15, but I wanted to see what you guys thought.

thanks guys! I also look forward to using this forum to help me with those tricky chemistry equations. I hate moles and imperial formula...


 

Offline Soul Surfer

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Fusion
« Reply #1 on: 23/11/2007 22:51:25 »
Zephyr  Your suggestions contain so many fundamental errors and misunderstandings that I am not prepared to put the effort into analysing them and explaining it to you.  Go back and learn a bit more physics and understand a bit more about the way nuclear fusion machines work before you think that scientists are not going about it in the best way that they possibly can but don't be afraid of asking simple questions elsewhere in this forum that will help you understand things a bit better.
 

another_someone

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Fusion
« Reply #2 on: 24/11/2007 00:08:18 »
I cannot say I understand all the assumptions you are making, but I will try and make some suggestions where I think you might be going wrong (I am sure others have much better knowledge of the relevant field than I, and can probably correct me in a number of places).

Firstly, you might want to read: http://en.wikipedia.org/wiki/Tokomak to understand something of the kind of solutions that are presently in place (they are not the only attempts being made at fusion power, but they seem to be the ones coming closest to the area you seem to be exploring).

Firstly, you seem to be confusing electric charge with electric current.  Electric charge is what surrounds each and every electron (or proton, or other charged particle - but usually we deal with electrons).  A current is the movement of this charge - but the charge itself exists without any movement at all.

I am not sure what you mean by a charge having a field of its own.  A stationary charge is just a stationary charge.  A moving charge (i.e. an electric current) will generate a magnetic field, this magnetic field depends on how much charge you have, and how fast it is moving.

If you look at the work on the Tokomak, you will see that all the effort is in keeping the plasma in the centre of the doughnut, and this is done by having the magnetic field of the current within the plasma interacting with magnetic fields around the doughnut.  The plasma cannot be allowed to touch the sides of the doughnut or it will lose all its energy.  My understanding is that part of the problem is that the interactions between the magnetic field of the current in the plasma and the surrounding magnetic fields is quite complex, and the plasma finds ways of leaking out of the confinement and hitting the side of the doughnut, and then collapsing.

Your particular issue about using the electric current to heat the plasma for fusion is covered in the following paragraph:

http://en.wikipedia.org/wiki/Tokomak#Ohmic_heating
Quote
Since the plasma is an electrical conductor, it is possible to heat the plasma by inducing a current through it; in fact, the induced current that heats the plasma usually provides most of the poloidal field. The current is induced by slowly increasing the current through an electromagnetic winding linked with the plasma torus: the plasma can be viewed as the secondary winding of a transformer. This is inherently a pulsed process because there is a limit to the current through the primary. Tokamaks must therefore either operate for short periods or rely on other means of heating and current drive (although there are also other limitations on long pulses). The heating caused by the induced current is called ohmic (or resistive) heating; it is the same kind of heating that occurs in an electric light bulb or in an electric heater. The heat generated depends on the resistance of the plasma and the current. But as the temperature of heated plasma rises, the resistance decreases and ohmic heating becomes less effective. It appears that the maximum plasma temperature attainable by ohmic heating in a tokamak is 20-30 million degrees Celsius. To obtain still higher temperatures, additional heating methods must be used.
 

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Fusion
« Reply #2 on: 24/11/2007 00:08:18 »

 

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