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FAQ - The Sun versus the Fusor

Posted: Thu Dec 31, 2009 5:44 pm
by Richard Hull
I have pulled together some data mainly from reliable books and also from NASA and Solar observatory websites. I wished to do the math and figure stuff out based on a recent posting related to the sun and put it in FAQ form.

Anyway, check my math guys.


The Sun

Solar energy output each second = 386 yotta joules/sec 3.86 X10e26 joules/sec
Solar volume 2.7403 X 10e18 cubic kilometers
Solar fuel (mass) 1.989 X 10e30 kg

Output energy per unit mass 3.86 / 1.989 = 1.94 X 10e-7 joule per gram per second or……~0.2 micro-joule/gram/sec

Output energy per unit volume 3.86/2.74 = 1.4 X 10e8 joules per cubic kilometer per second. Lets move that to cubic centimeter volumetric.
A cubic meter has 10e6 cc in it and a cubic km has 10e9 cubic meters so a cubic km has 10e15 cc in it. Thus the solar output energy per cc is 1.4 X 10e-7 joules per cc or….
0.14 micro-joules/cc

The sun, for our purposes, will be called a functional fusion reactor consisting of just fuel that is self bound and contained, for the most part.

Much quibbling, erudite point making and general trolling is possible about solar boundries, burnable mass, etc., but the above facts are what scientists have quoted as the accepted energy, diameter, volume and mass so it's what I am rolling with.


The Fusor ( Fusor IV stats)

Energy output at 1 million neutrons/ sec
This is 2 million fusions 1 million X 4.03 mev and 1 million X 3.27mev
Total of 4.03 X10e12 ev + 3.27 X 10e12 ev = 7.3 x10e12ev
1 ev = 1.6 x 10e-12 ergs. The total energy in fusion per second is 11.68 ergs/sec
(Have I mentioned I like ergs n' dynes)
1 joule/sec = 10e7 ergs/sec or 11.7 X 10e-7 joules/second

So a running fusor IV at 1 million neutrons/second produces 1.17 microjoules of fusion energy per second.

Now to figure the mass of fuel on hand in a running fusor and its volume. I work at about 8 to 10 microns in my running 6” diameter fusor at 1mega neut/sec.

Reactor fuel volume of fusor IV

4/3 pi x R^3 = 4.18 X 7.6cm^3 = `1850 cc of fuel volume

D is atomic weight 2 but the molecule is mass 4 so 22.4 liters of D fuel at STP is 4 grams.
At STP the fusor will hold 4 X 1.85/22.4 = .33 grams of d as fusible ions. However, we operate at ~ one 100,000th of an atmosphere.

So, the total fusible mass in the reactor is 3.3 X10-6 grams.


Now to do solar comparisons.

The fusor produces 1.17 x10e6/3.3 x 10e-6 or .35 micro-joules/gram/sec of fusion energy

Thus fusor IV, as a reactor, out produces the sun as a reactor, per unit of fuel mass present, in said reactor by 75%!!

The above fact is no doubt due to a lot of the solar mass, (fusion fuel), residing in more tenuous, cooler regions

The fusor loses out on overall volumetric efficiency, however, as it produces
1.17/1850 or only .00063 micro joules per cc per second. This makes the sun about 222 times more volumetrically efficient as a fueled fusion reactor that fusor IV.

The above fact is no doubt due to the extremely dense fusing core in the sun.

In summary:

We can at least proudly say that our fusors produce 75% more energy per unit fuel mass in our reactors than the solar fusion reactor, itself!!

Like any good, non-self respecting, lying-assed, dispeptic fusioneer we might neglect to tell of the poor comparative, volumetric efficiency. That's right, just razzle-dazzle 'em into th' tent like any good fusion barker would do.

Richard Hull

P.S. make replies of a corrective math nature or to add other interesting facts I might have left out. Of course, boundless praise is always held in high regard. RH

Re: FAQ - The Sun versus the Fusor

Posted: Thu Dec 31, 2009 6:11 pm
by Quantum
Richard, may I be the first to offer you the praise you so richly deserve.

However, the other post to which you refer related to calculating the energy required to produce a plasma with a density similar to the core of the sun, thereby achieving thermonuclear conditions comparable to the centre of the sun.

Yours is a very interesting post, though.

Re: FAQ - The Sun versus the Fusor

Posted: Thu Dec 31, 2009 6:34 pm
by Richard Hull
I just got the idea from the solar related posting. This is not a continuation of anything even obliquely related to that post. It was just a seed for this fresh idea of a reactor vs. reactor mathematical comparision.

It is as I always thought....The sun is a big loser by most any desireable earth based standard of fusion energy. About the only thing it's got going for it is it is a free 400 yotta joule energy source, it is self contained, self-igniting, self-running, it has fused for billions of years and will continue to fuse for billions more. Nothing like our glorious fusors that are microscopic is size, by comparision, with higher fusion energy to mass output and demand billions of times more energy to be jammed into them than we will ever get out and are tough to keep going for more than a few tens of minutes.

(tongue set well in cheek)

Yes, Virginia there is always a heapin' helpin' o' bad news with the good.

Richard Hull

Re: FAQ - The Sun versus the Fusor

Posted: Fri Jan 01, 2010 8:14 pm
by Chris Bradley
If you liked this post, you might also like to read one I did some time ago;


and also my observations;


neither of which are meant to be strict scientifically-evidenced back-of-envelope stuff for peer review, but you'll get the general idea!

Re: FAQ - The Sun versus the Fusor

Posted: Fri Jan 01, 2010 8:42 pm
by Quantum
Chris, once again I'd like to point out that the sun's density is not uniform.

I believe you've not taken this into account.

It would be no good replicating the 'average density' of the sun, as most fusion occurs in the higher density regions ie the centre.

Gravity is the 'driving force' here, and surely any comparison has to take gravity into account.

There are theories that suggest that 'mass' is a fifth dimension, and that the properties associated with mass (inertia, gravity, etc) can't be understood without an understanding of this.

To simply say 'condensing' some plasma to the average density of the sun will produce the average fusion rate in the sun doesn't follow.

Re: FAQ - The Sun versus the Fusor

Posted: Fri Jan 01, 2010 11:52 pm
by Chris Bradley
Ash Small wrote:
> To simply say 'condensing' some plasma to the average density of the sun will produce the average fusion rate in the sun doesn't follow.

Then don't say it if you don't like it!

These are *my* posts! I welcome *constructive* comment on the myriad of assumptions or technical limitations that are obvious to most, so I don't need your *approval* or otherwise! The purpose of embellishing comments with numbers is to provide the reader the chance to get a feel for the scales and to go away and improve on the loose accuracy I applied to my quickie calculations. It's not my job to run through pages of scientific numbers, I'm merely writing numbers down as I type the post with the purpose of illustration of the points, and a lack of precision suitable for *Journal publication* and Nobel prize-winning dissemination is inevitable but utterly immaterial to the objective.

Come up with your own figures, to which I may say 'yeah' or 'nay' as to whether I see them as an improvement on my own. What I have suggested are [I feel] novel, original comments with an already admitted level of finger-in-air but nonetheless with some figures one might contemplate for general order-of-mag.

You are behaving a bit like a leech, sucking out the blood of other people's ideas then telling them how bad it tastes!! Just come up with your own ideas, run your own numbers, and tell us something new - rather than saying everyone has just done or said what you have already suggested (which you seem to do regularly and that I cannot see the connection with your prior posts most of those times).

Re: FAQ - The Sun versus the Fusor

Posted: Sat Jan 02, 2010 12:23 am
by Quantum
Chris, I was trying to be constructive.

I was pointing out that the density of the sun isn't the same at all points, and that your maths doesn't appear (to me) to take that into account.

I realise it was a 'rough and ready' calculation, I notice you don't find fault with my reasoning.

I was merely pointing out that the density of the sun is much, much greater at the centre than it is at the edges, due to gravity.

While I also appreciate that gravity isn't really relevant to fusors, it is relevant to thermonuclear fusion in the sun.

People have 'introduced' theories on gravity on this site in the past, without criticism, so I don't regard that as an issue.

The same is true of the earth. density is not a constant all the way through, it is more dense at the centre.

I was merely suggesting that 'average density' is pretty meaningless in thermonuclear plasmas, where most fusion occurs close to the centre, probably with none occuring at the edges.

In order to create a mathematical model of the sun, you surely need to address this concept.

I certainly didn't mean any offence, Chris.

Re: FAQ - The Sun versus the Fusor

Posted: Sat Jan 02, 2010 1:03 am
by JamesC
>I certainly didn't mean any offence,

But offence you have given. Maybe you dont realise it but you have become quite annoying on this list but perhaps you dont know why so I will tell you clearly.

For months you have been highjacking , fragmenting and sidetracking forum thread after forum thread into irrelevent unresearched sideshows corrupting the stream of thought the original threads represent reducing their value to others. Its very selfish of you.

How about starting a new thread each time you want to inject yourself into an otherwise thoughtful thread and if others want take up your thoughts they can do so in your own seperate thread.

If you reply to this hint on this thread you will categorise yourself as a troll in my view

Re: FAQ - The Sun versus the Fusor

Posted: Sat Jan 02, 2010 1:35 am
by Quantum
James, you can't find fault with my reasoning, so you resort to insults.

Criticize my reasoning, or don't bother posting.

Or do you really think the density of the sun is the same at the edges as it is at the centre?

Re: FAQ - The Sun versus the Fusor

Posted: Sat Jan 02, 2010 3:34 am
by Kade
Just a little bit of trivia to add to the astronomical numbers that mass seems to have when you are discussing the sun, It is interesting to make a comparison between the electrostatic forces and the mass related gravitational forces, and relaize how much more electrostatic force is available from a very small mass than gravitational force.
2* 2 gram bottles of ionized hydrogen (i.e. 2 grams of ions 10 to the 24 elementary charges), placed on opposite sides of a diameter of the earth will repell each other with a force of about 50 tons. Helps to explain perhaps why electrostatic confinement is more "Edit Mass" efficient than the sun when it comes to fusion.
Edit: I guess this means that if a fair amount of the sun is comprized of ions, the gravitationally related pressure near the center could get pretty low!