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Disposal of radioactive materials

Posted by: slycker - Thu Dec 02, 2004 10:33 pm
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Disposal of radioactive materials 
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Post    Posted on: Sun Jan 02, 2005 5:16 pm
I don't argue because of the required amounts of propellant - I#m doing the mathematics to see wether I will get a spiral course.

All the other points concerning the possibility to move it to another star I do mention only to keep this thread from being complicated by this idea which in practice noone will try I hope.



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)


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Post    Posted on: Sun Jan 02, 2005 5:28 pm
I only mention travel to another star as an example of a very high energy requirement.

Have you tried the one hour per step calculation yet? Calculating seond by second is really not necessary.


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Post    Posted on: Mon Jan 03, 2005 1:59 pm
No - I got back the excel file and have continued the calculations.

A portion of the resuts I already have added under "Step Two" by EDIT. For the first time only 20 repetitions of the calculations for 65536 seconds are required to see what will happen. Now the file has become to big because of data only - no problem.

Dipl.-Volkswirt (bdvb) Augustin (Political Economist)

EDIT: Step Two is ready now - except my own check for errors in my issues.


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Post    Posted on: Mon Jan 03, 2005 7:17 pm
Ekkehard Augustin wrote:
For the first time only 20 repetitions of the calculations for 65536 seconds are required to see what will happen. Now the file has become to big because of data only - no problem.

If you calculate 19 one hour steps instead of 65536 one second steps your file will not become too big.


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Post    Posted on: Tue Jan 04, 2005 8:51 am
You seem not to have read my edits - the 20 repetitions are ready. I got back the orginal excel file and seperated it into several parts. The first and orginal file I now use for calculations only. The results I store into additional excel files - I know the results for each single second of the 13,000,000 now.



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Post    Posted on: Tue Jan 04, 2005 3:02 pm
Ekkehard Augustin wrote:
The results I store into additional excel files - I know the results for each single second of the 13,000,000 now.


Yes I did read your edit, but if you have results for each single second then you are not using my suggestion. You only need one result for each hour, not one for each second.

(EDIT) By the way, I just checked your calculation with the orbital energy equation. At the 1.3 million second point from your Dec. 28 post, a distance of 135,000,000 (rounded from your 135,045,309 to 135,045,292 km range) and speed of 34 km/s the orbital energy is still correct. So your calculations look good so far.

(ANOTHER EDIT) Using orbit.xls I predict your orbit will reach a perihelion distance of about 117,750,000 Km after about 5,800,000 seconds and then start moving farther from the Sun again. Since you have already gone 13 million seconds, how do my predictions compare with your results? What distance and velocity do you have now at 13,000,000 seconds?

(OOPS, CORRECTION EDIT) I made some calculation errors. After re-checking I find that a 7.74 km/s velocity toward the Sun added to the Earth's orbit should result in an initial orbital energy of -420. After 1.3 million seconds your resulting orbital energy is -405 and mine is -421. So we are both close but with small errors in opposite directions.


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Post    Posted on: Thu Jan 06, 2005 7:41 am
Your answer is sounding like you have a concrete image of what I have in mind and you take it as selfunderstanding. So I should clarify a little bit what I have in mind.

I didn't use any additional acceleration since the launch of the vehicle carrying the package of radioactive materials - but this doesn't mean that there will no additional acceleration during the next steps.

In opposite - I have in mind additional accelerations to be calculated later. The only reason not to accelerate by engines during step two is that the initial acceleration would cause a course tangential to one concrete orbit if there were no gravitational acceleration. But there is gravitational acceleration and so I wanted to provide a comparison.

In step three I will do something special - what it will be I decide when I'm ready with checking for errors and correcting them.

There will be a special situation after one of the following steps - it will include a difference concerning a special circumstance.

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Post    Posted on: Thu Jan 06, 2005 10:44 am
Well, I'm back from vacation, and have finally thrown together that VB code mentioned about 5 pages back. Unfortunately, however, after many hours of bug-hunting, my finished product is both horribly slow (slow graphics, it seems) and painfully difficult to use (no time to optimize while debugging, as it was so horribly slow and I'm on a 2.4ghz machine). It seems as though Ekkehard has a concrete grasp of what orbit.xls is showing, so then a little animated orbit application seems of little use. I am very happy to let this one die (and yes, I had a lot of dust on my VB knowledge, and everything seems to have changed in the new .NET version).

To force a slight return-to-topic,
So a plain decent to the sun would be very propellant-costly. Couldn't a Jupiter Gravity Assist greatly help with this? If so, then why sweat so much about exactly how much propellant it would cost to slowly degrade an orbit ('spiral', if you will) while continually firing engines to slow the craft down.

Camphelp,
You had mentioned how crashing the payload onto jupiter would be relatively simple. Is this notably simpler than using a JGA to crash into the sun?

Does anyone have any numbers on the rate of radioactive waste production? How about mass of already produced waste? (for any of North America/Europe/China/Russia)

I'm hoping that when the EU and Japan finish bickering over the location of the Fusion reactor, that this new form will eventually drastically decrease this rate of waste production.


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Post    Posted on: Thu Jan 06, 2005 11:27 am
Hello, slycker,

from my informations about a launch by a space elevator and the pulsed fusion drive it doesn't seem up to now that the plain descent to the sun would be very propellant-costly.

The pulsed fusion drive uses mini- or micro-fusion-bombs - according to Ulrich Walter. There will explode hundreds or thousands of such bombs behind the spacecraft and their pieces and the fusion products will impact a magnetic field at the end of the spacecraft to accelerate it.

Mini- and micro-fusion-bombs - much smaller than the known fusion bombs. Such small bombs don't be of any use in any war - they will cost much less than fusion bombs designed for war and they will be produced by numbers causing significant economies of scale.

Nanotechnology may be invloved in such small bombs perhaps - or it may be going to be involved.

So up to now I really don't see the high propellant costs. If there will be such spacecrafts in the future they will be reusable I think - so they can be used to throw something into the sun as well as for other purposes.

And up to now I didn't accelerate the vehicle by that drive in my mathematics - there were only the elevator in action during step one.



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Post    Posted on: Thu Jan 06, 2005 3:24 pm
Hi slycker,

Yes, crashing the waste into Jupiter would be much better than going for the Sun. However I can’t see current technology becoming cheap and reliable enough any time soon to make even that option a good idea.

Hi Ekkehard,

You can slowly spiral down with continuous thrust. Frequently repeated thrust events could also approximate a spiral. However this method has been shown mathematically to cost MORE propellant than just entering an elliptical orbit to go the same place. Here is a link to the mathematical proof:
http://en.wikipedia.org/wiki/Hohmann_tr ... t_transfer
(see the Low-thrust transfer topic near the end of that page)

Also, production of fusion bombs requires producing fission bombs, because all current fusion bombs use a fission bomb as the trigger. And production of fission bombs produces nuclear waste!


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Post    Posted on: Fri Jan 07, 2005 12:05 pm
Ulrich Walter explicitly says that the microfusionbombs would be ignited by laser - and not by fission bombs. No production of fission bombs is required for this purpose and no nuclear waste by fission bombs will occur.

And up to now in my mathematical calculations there has been no consumption of propellant. Pleas wait for what will happen - then a calculation of the costs can be done.

The calculations up to now only have the purpose to look if I will get a course going spirally in popular sense. If I get one it should be optimized under the aspect of costs. And only the package will fall into the sun - not the vehicle.

A word concerning the error in my calculations: I have to do additional trigonometrics. The calculations are assuming that the initial acceleration by space elevator and all the gravitational acceleration allways will go to the same direction - that's wrong. Except the first second there will be an angle of less than 180° between the elevator-caused acceleration and the permanent gravitation-caused accelerations. This angle will become narrower second by second. This is causing the elevator-caused vector pointing to the sun to become smaller and smaller.

So I have to correct my calculations - the distance to sun will not be that close, the velocity will be less and the angle will be greater.



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Post    Posted on: Fri Jan 07, 2005 8:38 pm
Ekkehard Augustin wrote:
I have to do additional trigonometrics. The calculations are assuming that the initial acceleration by space elevator and all the gravitational acceleration allways will go to the same direction - that's wrong.

This problem is because your method of calculation does not address a radial velocity at all. It assumes a circular, or nearly circular, orbit and does not work for other shapes.


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Post    Posted on: Sat Jan 08, 2005 1:30 pm
The reason doesn't have anything to do with waht you are mentioning - I simply didn't remark a mathematical requirement caused by geometry.

The error cannot have anything to do with th shape because I don't use any shape-related formulars. Once the vehicle had been launched the earthian orbit doesn't have any meaning for the calculations. The assumption of a nearly circular orbit has been of meaning only to get starting consitions If I had assumed the vehicle to be launched from a planet going an elliptical orbit the current calculations would go the same way - only some numbers would change. What would have been different is the way to get the starting conditions.

In between I'm working at the corrections - the numbers are changing but not as much as I expected.



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