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Re: tesla and fusion

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Hi Chris,
I believe this is possible. If you are fusing two deuterium atoms, the required energy is around 144000 ev. If you ionize the deuterium and reduce the pressure so the mean distance between collisions allow for this energy to obtained in an electric field, then you probably will get the particles to fuse once in a while. They will need an almost a perfect head on collision since the fusion cross section is roughly the size of the nucleus (a proton and a neutron) measured in barns (10^-24 square meters). However, there are two conflicting requirements for efficiency. First, you need to get the energy into the particle (lower pressure means more energy) Secondly, the mean distance between fusion collisions need to be short to get much energy from it (higher pressure means more collisions). The higher the gas pressure, the stronger the field strength needed to impart the required energy. My text book doesn't talk about the limits of this. Also, deuterium-deuterium collisions require a much higher energy level to get a certain fusion cross section (0.1 barns requires 1000 kev). A deuterium-tritium collision only requires 100 kev for a 1 barn cross section. 

Gerry R.


Original poster: "Chris Rutherford" <chrismrutherford@xxxxxxxxxxxxxx>
Fusion from electricity has been proven to work, take the Farnsworth Fusor for example. This can be made with basic materials and such as a HV source and a vacuum pump. Numerous people have measured neutrons coming from this device, proving that the " 40 -100 million degrees Kelvin" is being reached. Unfortunately due to inefficiency it never reaches over unity. Maybe it doesn't reach the 1Bn K for mass fusion? 

<http://en.wikipedia.org/wiki/Fusor>http://en.wikipedia.org/wiki/Fusor
A modification to the Fusor is to replace the grid/gause at the centre with a series of external magnets to accelerate the electrons to the center and create the "electron well", which in turn accelerates the positive ions through the centre in a figure of 8 motion, conserving energy and accelerating all the time. Some Deuterium ions collide in the center with enough "heat" to overcome the coulomb barrier and fuse. This was shown to have results around 1000 times better than the fusor. 

This vid about the magnetic Fusor is interesting

<http://video.google.co.uk/videoplay?docid=1996321846673788606>http://video.google.co.uk/videoplay?docid=1996321846673788606
In concussion, can fusion be done with a TC, YES. Can it be sustainable and over unity, Yet to be proven. 

Thanks

Chris Rutherford
Original poster: "Gerry Reynolds" <<mailto:gerryreynolds@xxxxxxxxxxxxx>gerryreynolds@xxxxxxxxxxxxx > 

Hi Steve,

You may be interested to know that in order to get two interacting
particles to fuse, the nuclei need to approach within an order of
10^-14 m.  This is about 1/10000 of the diameter of a hydrogen
atom.  The nuclear radius of a particle is generally taken to be
1.5*10^(-15)*A^(1/3) where A is the atomic weight of the particle (A
needs to be less than 20 for fusion to occur). The obstacle to having
this occur is the coulomb barrier.  In order to have enough kinetic
energy to over come this barrier and get to about 10^-14 m, the
kinetic energy needs to be:

Ue = 1.44 * 10^5 * Z1*Z2 ev

where Z1 and Z2 are the atomic numbers of the two interacting particles

The temperature needed to get great numbers of fusion reactions is
about 1 billion degrees Kelvin.  The temperature needed to get some
reactions can be as low as 40 million degrees Kelvin but generally it
is thought that 100 million degrees Kelvin is needed for fusion.

Gerry R.