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Could you stand living in a scout ship?

Corrected Data on Fission verses Fusion Energy Yield

The following information on energy yield of fission and fusion reactions is taken from The Effect of Nuclear Weapons, 1977 Edition, edited by Samuel Glasstone et al., and can be located here:

http://www.abomb1.org/nukeffct/index.html

It is:

This is the definitive, unclassified text on nuclear weapons effects.

I am more familiar with it as DA Pam 50-3.

Complete fission of 0.057 kg (57 grams or 2 ounces) fissionable material

Fission of 1.45 x 10(exp25) nuclei
10(exp12) calories
2.6 x 10(exp25) million electron volts
4.48 x 10(exp19) ergs (4.18 x 10(exp12) joules)
1.16 x 10(exp6) kilowatt-hours
3.97 x 10(exp6) British thermal units

From this, the complete fissioning of 2 ounces of U-3=235 (57 grams) yields 1.16 Million Kilowatt hours of electricity.

In the following quote, D stands for Deuterium, T stands for Tritium, He is Helium, either 3 or 4, and H is straight Hydrogen.
1.69 Four thermonuclear fusion reactions appear to be of interest for the production of energy because they are expected to occur sufficiently rapidly at realizable temperatures; these are:

D + D = He-3 + n + 3.2 MeV
D + D = T + H + 4.0 MeV
T + D = He-4 + n + 17.6 MeV
T + T = He-4 + 2n + 11.3 MeV,

where He is the symbol for helium and n (mass = 1) represents a neutron. The energy liberated in each case is given in million electron volt (MeV) units. The first two of these reactions occur with almost equal probability at the temperatures associated with nuclear explosions (several tens of million degrees Kelvin), whereas the third reaction has a much higher probability and the fourth a much lower probability. Thus, a valid comparison of the energy released in fusion reactions with that produced in fission can be made by noting that, as a result of the first three reactions given above, five deuterium nuclei, with a total mass of 10 units, will liberate 24.8 MeV upon fusion. On the other hand, in the fission process, e.g., of uranium-235, a mass of 235 units will produce a total of about 200 MeV of energy (¤ 1.43). Weight for weight, therefore, the fusion of deuterium nuclei would produce nearly three times as much energy as the fission of uranium or plutonium.

In my earlier post, I did not include the D + T reaction, but because it is highly likely to occur, I should. On a weight for weight basis, 235 units of Deuterium will yield 582.8 MeV of energy, compared to either my earlier figure of 215 MeV for U-235 fission, or Glasstone's 200 MeV for U-235 fission. Using Glasstone's figure, as the more conservative, that would give an equal weight of Deuterium 2.914 times the energy of U-235. This would mean that the complete fusion of 2 ounces or 57 grams of Deuterium would 3.38 Million Kilowatt-hours of electricity.

Therefore, the complete fusion of One pound or 453.6 grams of Deuterium would yeild 27.04 Million Kilowatt-hours of electricity. That would give 3,086.75 Kilowatts of power per hour of a 365 day year with 24 hours per day. The complete fusion of 2.2046 pounds of Deuterium or 1 Kilogram, will yield 6,805 kilowatts of electricity per hour. Remember that is the fusion yield for a year of 2.2046 pounds/1 kilogram of Deuterium. I suspect that one kilogram of Deuterium per year would supply the basic ship power for a Scout Ship, or a much larger ship for that matter.

Based on all of this, I would say that providing 1 Traveller dTon for Liquid Deuterium would be more than adequate for supplying the base power of a small star ship for one year. As a Traveller dTon of Liquid Deuterium would weight 2192.4 kilograms, more than twice the weight of Liquid Hydrogen, that would give an ample fuel reserve. For my small-ship universe, I think I will go with 1 dTon of Liquid D times hull size divided by 1,000 rounded up, with a minimum of 1 dTon. That does not include fuel for Maneuvering however, just the typical ship power load. I will have to work on the fuel for Maneuvering next.
 
For my small-ship universe, I think I will go with 1 dTon of Liquid D times hull size divided by 1,000 rounded up, with a minimum of 1 dTon. That does not include fuel for Maneuvering however, just the typical ship power load. I will have to work on the fuel for Maneuvering next.

I find the reinvention of TNE's FF&S amusing....:coffeesip:
 
In CT 77/HG1 the power plant fuel is for reaction mass (plus a little bit for electricity production no doubt).
The formula CT formula is nonsense, but go with the HG1 0.01 x Hull tonnage x power plant number and there you have your reaction mass.

TNE authors wanted to go back to the reaction drive model, hence heplar, so to marry TNE and CT together the power plant fuel formula from HG1 becomes the fuel for 24 hours at full thrust.

If you want more maneuver time start using your jump fuel as reaction mass (which was another thing the TNE authors wanted back - players making choices based on a limited resource).

The power plant is effectively free of its own fuel requirement (top up at annual maintenance should do it).

This is how I do it IMTU.
 
sf does not mean square feet? I guessed Artpollard has already accounted for the ceiling heigh and told about the surface in quare feet...

It does... but cf is cubic feet, and cubic feet to cubic meters requires a known ceiling height.
 
I find the reinvention of TNE's FF&S amusing....:coffeesip:

As I never got into Traveller: The New Era, I am afraid I miss the humor. Besides, figuring it out myself keeps me busy, not getting into trouble, and results is the satisfaction of determining it myself.

Now if I can just figure out a plausible small fission plant for larger vehicles, otherwise, in my Traveller Universe, they still will be using petroleum or the like. Not that such use represents a problem, just that it does limit range a bit. I just cannot visualize a small fusion plant. With HBP's "collapsium" I can make it work, but "collapsium" is not around in Traveller. Maybe an inwardly focused "black globe" screen that has some holes in it for controls? Have to work on that.
 
In CT 77/HG1 the power plant fuel is for reaction mass (plus a little bit for electricity production no doubt).
The formula CT formula is nonsense, but go with the HG1 0.01 x Hull tonnage x power plant number and there you have your reaction mass.

TNE authors wanted to go back to the reaction drive model, hence heplar, so to marry TNE and CT together the power plant fuel formula from HG1 becomes the fuel for 24 hours at full thrust.

If you want more maneuver time start using your jump fuel as reaction mass (which was another thing the TNE authors wanted back - players making choices based on a limited resource).

The power plant is effectively free of its own fuel requirement (top up at annual maintenance should do it).

This is how I do it IMTU.

So if the fuel is water then steam powered space ships?

Which sparked another thought - orbital stations firing ships in the direction they want to go via a kind of tunnel rail gun.

edit:

I appreciate the chance of this being scientifically plausible is probably zero but I was struck by comments about the problem with fusion engines currently is all they produce is heat so it would be very funny if a fusion powered steam engine was a viable thing.

Space 1899 for real.
 
The spaceship in Destination Moon used water heated by a nuclear reactor for its reaction mass. High-purity Hydrogen Peroxide, like in concentrations 60% or higher, with the remainder water, when decomposed, turns into very hot steam and oxygen, and can be used as a monopropellant for not extremely powerful rockets. Spaceships powered by super-heated steam are perfectly reasonable. After all, with the US Space Shuttle burning oxygen with an excess of hydrogen, the exhaust was super-heated steam and very hot hydrogen.
 
The titular ship in Rocket Ship Galileo by Heinlein used Zinc heated to steam by a nuclear reactor that used Thorium as the fissionable material for it's thrust.
 
Hmm, Rocket Ship Galileo. It has been a long time since I read that. One of the first science fiction books that my oldest brother brought home to read from the library, and that I snagged.
 
The titular ship in Rocket Ship Galileo by Heinlein used Zinc heated to steam by a nuclear reactor that used Thorium as the fissionable material for it's thrust.

Missed that, interesting it's not a new idea. I thought it was a recent steampunk thing.
 
As I never got into Traveller: The New Era, I am afraid I miss the humor. Besides, figuring it out myself keeps me busy, not getting into trouble, and results is the satisfaction of determining it myself.

It, more about doing the math and coming to similar conclusions. And for the record SJGs got to the same place with GURPs Space.
 
The actual 'living space' is even smaller than that ... 4 staterooms = 16 dTons = 800 sf of living area = efficiency apartment ... with 4 people locked in for 1 week.
800-square-foot-apartment-floor-plan.jpg

Well, my office downstairs is approximately stateroom size, and its connected to the living room. A mess and washroom / shower are nearby. If I multiply my office by four, surround the living area, and keep the kitchen / mess and WC, and ignore all of the upstairs, then I got my scout interior, with the garage acting as the cargo area.

It's more than doable, but they wouldn't by luxury accommodations by any stretch of the imagination. Of course, if you're wealthy enough to own or lease a scout, then maybe money's not that much of a barrier in the first place, in which case you can deck out your interior with some luxury furniture.
 
It doesn't?

/snips/

Now if I can just figure out a plausible small fission plant for larger vehicles, otherwise, in my Traveller Universe, they still will be using petroleum or the like. Not that such use represents a problem, just that it does limit range a bit. I just cannot visualize a small fusion plant. With HBP's "collapsium" I can make it work, but "collapsium" is not around in Traveller. Maybe an inwardly focused "black globe" screen that has some holes in it for controls? Have to work on that.
I always thought in the OTU "bonded superdense" was what they called "collapsium" in Piper's works. Am I wrong and if so, what is the difference?
 
I always thought in the OTU "bonded superdense" was what they called "collapsium" in Piper's works. Am I wrong and if so, what is the difference?

Here is how Piper described "collapsium" in Four Day Planet.

Most of the weight was on the outside; a dazzlingly bright plating of collapsium—collapsed matter, the electron shell collapsed onto the nucleus and the atoms in actual physical contact—and absolutely nothing but nothing could get through it. Inside was about a kilogram of strontium-90; it would keep on emitting electrons for twenty-five years, normally, but there was a miniature plutonium reactor, itself shielded with collapsium, which, among other things, speeded that process up considerably. A cartridge was good for about five years; two of them kept the engines in operation.

I had to dig out my copies of Striker and MegaTraveller for the "bonded superdense". According to those, "bonded superdense" is partially collapsed matter with reinforcing electrical fields. "Superdense" is partially collapsed matter, not sure if it is being maintained by an artificial gravitational field or not, the rules are not that clear.

Basically, Piper's "collapsium" is fully collapsed matter, the other two are partially collapsed matter. One is basically neutron matter, the other is matter with the atoms forced closer together by a "massive artificial gravity field." Not sure how you keep the atoms forced closer without an external field. I guess I would prefer "collapsium", but it looks like I could use it in My Traveller Universe.

From MegaTraveller, it looks like "superdense" is about 4 times stronger than hard steel (whatever that is) on a weight basis (a weight factor of 0.26 is given), with "bonded superdense" being about 7 times stronger on a weight basis (a figure of 0.14 is given). Bizarrely, both cost the same as hard steel, which considering the processes required to produce said armor, is, as stated, bizarre. Then again, "soft steel" costs more in terms of weight, 1.25 times, as much as "hard steel". Soft steel is available at Tech Level 5, Hard Steel is available at Tech Level 6, Superdense is available at Tech Level 12, and Bonded Superdense is available at Tech Level 14.

Note on Armor Development: Mild steel was being used as a material for shipbuilding starting about 1880, with nickel steel alloy armor and Harvey and Krupp Face-Hardened Armor in the 1890's. High Tensile Strength steel for ship-building and armor appears shortly after 1900 and was used in World War 1. The US Navy developed Special Treated Steel as both a ship-building material and armor in the 1930's, and then in the early 1940's came up with a vanadium alloy steel for submarines that boosted crush depth from 600 to 800 feet for the same thickness. However, all of these cost more than mild steel, which is presumably "soft steel", in some cases by a factor of 5 or more with respect to thick face-hardened high alloy plate. The price modifiers for armor in MegaTraveller are just plain weird.

Note on Piper's physics for power production: It does not work, but there is another way of doing it using a couple of different plutonium isotopes that would.
 
Basically, Piper's "collapsium" is fully collapsed matter, the other two are partially collapsed matter. One is basically neutron matter, the other is matter with the atoms forced closer together by a "massive artificial gravity field." Not sure how you keep the atoms forced closer without an external field. I guess I would prefer "collapsium", but it looks like I could use it in My Traveller Universe..

YMMV, but that's where I draw the line as "hand-wave-ium."

salochin999 said:
Missed that, interesting it's not a new idea. I thought it was a recent steampunk thing.

Which part? Fission heated, reaction-mass rockets?

Now I'm wondering whether sodium or water would be a better reaction mass. Timerover, in your apparent plethora of technical manuals, do you have a chart of ISPs for different materials?
 
YMMV, but that's where I draw the line as "hand-wave-ium."

YMMV? What does that mean?

Which part? Fission heated, reaction-mass rockets?

Now I'm wondering whether sodium or water would be a better reaction mass. Timerover, in your apparent plethora of technical manuals, do you have a chart of ISPs for different materials?

Water has a mass per molecule of 18, Sodium has a mass per atom of 23. The lighter the molecule or atom of reaction mass, the higher the specific impulse, and hence final velocity for equal mass-ratios. The optimum reaction mass is Liquid Hydrogen, which was proposed for use in nuclear-powered space ships in the 1960's, where it was used both as reactor coolant and reaction mass. One reason the Shuttle was burning excess hydrogen in its engines was to reduce the average molecular weight of reaction mass to increase specific impulse. The other advantages of water is that it is a liquid at normal temperatures, has the ability to absorb a lot of heat, and can be used to cool the exhaust nozzle of your reaction engine.
 
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