How do jump drives really work?

[Dragoner]

As you see, I assume water taken into fuel tanks (if any) is destilled, be it by producing it with hydrogen and oxigen or by destilling it when pumping from an ocean. If you fill your tanks with water taken directly from the sea, I guess bacterial corrosion whould be the least of your problems.

I would bet an osmotic filter over your inlet would be more efficient than distiliation.

Really I am only making an example of the new complex layer of problems that water cooling/tankage/fuel storage would bring. I haven't even touched Pipe diameter, impeller size and cavitation, etc. ; AND water still doesn't fufill the cooling needs, esp if we are talking 60% efficiency and 30,000Mw of waste heat needing to be cooled.

 

[E.D.Quibell]

Sure, that will work. In fact, it's the solution I've been advocating all along. I went with an Ancient artifact that provided the missing fuel and I still think that's the best way, but if you want to make it an Ancient artifact that can jump without fuel, that works too.

Hans

No Fuel isn't needed. Just Energy.

Drop tanks use all the fuel before jump.
Jump projectors are only powered by energy.
Black globes charge jump capacitors.
The Annic Nova has no fuel.
Jump nets cover non standard shaped cargo, in vacume.
Jump fuel volume requirments drops with increase TL.

They all point (suggest) to just energy being needed for jump. They all suggest that Jump fuel is just there to provide power and/or cooling and/or both and/or something in additon, but that it's _not_ there to provide for the jump.

So from what we know it's inefficent ... so what? It could be the easierst/best/chepest way to provide for jump on a dayin/dayout basis, and relying on the easiest element in the universe to refule and to get you out of trouble. But it's posible to do it other ways we know that that's why we are having the discussion.

And if an ancient artifact can jump without fuel then other things can too, it just might be harder to achieve at lower TL.

Best regards,

Ewan

 

[HG_B]

http://theweek.com/article/index/210233/the-bug-eating-the-titanic

Der, bacteria too, as well as dielectric decomosition.

Couldn't find info in there about bonded superdense. Is it the wrong link?

 

[shadowcat20]

Was looking through LBB 5 AHL class cruisers last night and noticed that it states right in the fuel deck that it stores LHyd and even shows the cooling units on the deckplans. AHL class cruisers do not seem to be set up to use water.

Just throwing a little H2 on the fire....:devil:

 

[robject]

Rancke, wouldn't the Annic Nova not break the OTU if it were sufficiently high tech? As long as the Imperium can't replicate it, there would only be the one, which shouldn't cause too much trouble.

Fuel isn't needed. Just Energy.
[...]
So from what we know it's inefficent [...] It could be the easiest/best/cheapest way to provide for jump on a dayin/dayout basis [...]

Traveller 5 clarifies jump rules with concepts similar to the above.

And, you can design the ANNIC NOVA, and ships like it, using T5. Don't expect to see them in the Imperium though.

 

[Dragoner]

Couldn't find info in there about bonded superdense. Is it the wrong link?

There could be handwavium bacteria as well.

 

[rancke]

Traveller 5 clarifies jump rules with concepts similar to the above.

You mean, they explain how the jump drive really works in the OTU and in what respects B2, HG, MT, TNE, T4, T20, GT, and MGT got it wrong?

And, you can design the ANNIC NOVA, and ships like it, using T5. Don't expect to see them in the Imperium though.

Why not? Tech level too low or something else?


Hans

 

[McPerth]

Wrong; they can be cultured in cooler water; most bacteria become dormant when chilled below culturing temps, not dead, too.

They cannot be cultured on cooler water, just kept (as you said they go dormant) for latter culture on better conditions. Anyway, dormant bacteriae aren't dangerous unless they go to better conditions for living and growing.

What is worse for them are pH and osmotic changes. Changes on it's tolerable (for them) pH kill them, as drastic changes on osmotic presure, either by lysis (as I explained) or by dissecating them if osmotic presure is too high.

I would bet an osmotic filter over your inlet would be more efficient than distiliation.

I don't think reverse osmotic filter whould suffice. You can produce drinkable water from salt water with those filters, but not destilled water, that is what you need if you want to avoid corrosion and precipitates.

It's per combat round. So 1kl of sink holds 650 Mw for 20 minutes, or 216.66r Mw hours.

13.5kl of sink is thus 2924.99r Mw hours

Regards,

Ewan

I know my calculations are argueable, and I said clearly it was an assumption. I underand your point of view, and I thought on it before writing my previous entries, but you must take on account that the same 20 min you say should be applied to the weapons firing.

If you have a spinal weapon that consumes 3000 Mw, I think its shoots are about 1000 Mw h each 20 min, as the power requirements are 3000 Mw h/h.
If they used 3000 Mw h/turn, you'd need a constant 9000 Mw supply.

As the same factor 3 (20 min turn against hours) applies to both, weapons and absorbtion by black globe, I just discarded it and assumed we can talk about Mw h equivalent. EDIT: Anyway, as my previous calculations told about 1% of the fuel burned and 99% to be accounted for, I don't think we should now begin a bitter argument for this change (0.3% burned and 99.7 to be accounted for).

If you want to put this factor 3 into the calculations, I think it should be used as divisor, not as multiplier, for your 3000 Mw spinal is just shooting 1000 Mw h/turn, and yet count as 3000 Mw absorbed, so the 650 Mw/kl stored should be 216.666666... Mw h/kl so 2924.99999... (let's say 2925) Mw h/dton.

Those calculations diminished to a third our previous ones, so only a third of the fuel said is consumed and more fuel has to be accounted for if we keep on canon fuel needs.

As an aside, if we make those calculations, a TL 13 nuclear missile (factor 2) whould release 16666.6666... Mw/h (25000 Mw absorbed per factor), so standard nuclear missile is 14.2 kton

 

[E.D.Quibell]

I worked up an MT 100 ship last night, with and without jump fuel, using the power plant to charge the jump capacitors inherent in a jump 1 drive, and the difference is big.

As Hans suggests it could seriously change the economic model. I got an additional 9.5 tons of cargo space in a 100 ton ship for a Cr 500,000 additional cost.

If you can charge the capacitors _while in jump_ or without maneuver running it would take about 4 hours. If you charge the capacitors with the maneuver drive running it would take 6 days. However that doesn't mean you couldn't put in a bigger power plant.

So there must be some reason why you can't charge the jump capacitors when in jump. However that wouldn't preclude you from installing another set of capacitors or another jump drive, or use the turn around time in port to charge you jump drive.

Turn around time for merchants would likley be the same. 100d to port, unload and charge capacitors, 100d to jump and then jump. Giving the same amount of jumps in a year. However rift jumping would be easy as you wouldn't need to find fuel, or the fuel you carry for your power plant would be sufficent to get you across. 30 days fuel at full maneuver equates to about 120 days with no maneuver or 100 days if you charge the jump drive 16 times with no maneuver.

Annual maintnance would be the same, fuel costs would be significantly less (no jump fuel), and cargo space (income) would be more.

So Hans' question is still valid. Why is it cheaper/better/faster to use jump fuel?

And if we could make the answer plausable then even better

Best regards,

Ewan

 

[McPerth]

If you want to put this factor 3 into the calculations, I think it should be used as divisor, not as multiplier, for your 3000 Mw spinal is just shooting 1000 Mw h/turn, and yet count as 3000 Mw absorbed, so the 650 Mw/kl stored should be 216.666666... Mw h/kl so 2924.99999... (let's say 2925) Mw h/dton.

Sorry, I missread you (reading while on a hurry is not allways a good idea). I see your calculations are the same as mine.

 

[robject]

You mean, [T5] explain how the jump drive really works in the OTU and in what respects B2, HG, MT, TNE, T4, T20, GT, and MGT got it wrong?

Right More a case of patching up the holes.

Why not? Tech level too low or something else?

Right, the ANNIC NOVA has a higher TL than the Imperium.

 

[rancke]

Right, the ANNIC NOVA has a higher TL than the Imperium.

I can live with that. In fact, it's probably a better way to go than my suggestion. But I do feel compelled to point out that this is also a subversion of the original adventure, where it is stated that the PCs can just register the Annic Nova with the authorities and go on with the life of the freetrader, without having excessive trouble finding people competent to maintain her and without the Imperium confiscating her or mentioning the option of selling her for an indecent amount of money to some sort of research facility for reverse-engineering.


Hans

 

[McPerth]

I worked up an MT 100 ship last night, with and without jump fuel, using the power plant to charge the jump capacitors inherent in a jump 1 drive, and the difference is big.

As Hans suggests it could seriously change the economic model. I got an additional 9.5 tons of cargo space in a 100 ton ship for a Cr 500,000 additional cost.

If you can charge the capacitors _while in jump_ or without maneuver running it would take about 4 hours. If you charge the capacitors with the maneuver drive running it would take 6 days. However that doesn't mean you couldn't put in a bigger power plant.

So there must be some reason why you can't charge the jump capacitors when in jump. However that wouldn't preclude you from installing another set of capacitors or another jump drive, or use the turn around time in port to charge you jump drive.

Turn around time for merchants would likley be the same. 100d to port, unload and charge capacitors, 100d to jump and then jump. Giving the same amount of jumps in a year. However rift jumping would be easy as you wouldn't need to find fuel, or the fuel you carry for your power plant would be sufficent to get you across. 30 days fuel at full maneuver equates to about 120 days with no maneuver or 100 days if you charge the jump drive 16 times with no maneuver.

Annual maintnance would be the same, fuel costs would be significantly less (no jump fuel), and cargo space (income) would be more.

So Hans' question is still valid. Why is it cheaper/better/faster to use jump fuel?

And if we could make the answer plausable then even better

Best regards,

Ewan

How long can those capacitors hold the energy?

Whould it not be lost in form of heat?

I see capacitors as capable to hold lots of energy, but only for a short time, and then release all in a very fast discharge, needed for the jump.

I understand AN capacitors must hold this energy quite more a longtime, but, based on the space available, they're perhaps quite bulky (IDK), as the solar pannels whould not take as much volume, if we take MT numbers.

What I try in this thread is how to explain the huge amounts of fuel needed by JD (according to canon), for we have calculated only a mere 1% (or 0.333...%) must be burned.

 

[rancke]

How long can those capacitors hold the energy?

The ones from the Annic Nova? A minmum of six weeks, since it's possible to charge them over six weeks. By inference, at least long enough to perform one jump and get some useful me time in the next system before jumping out again (A full charge can power a jump by each of the AN's two jump drives; this wouldn't be useful if the charge didn't last long enough to perform the second jump).

I see capacitors as capable to hold lots of energy, but only for a short time, and then release all in a very fast discharge, needed for the jump.

That's how standard capacitors work, yes.

I understand AN capacitors must hold this energy quite more a longtime, but, based on the space available, they're perhaps quite bulky (IDK), as the solar pannels whould not take as much volume, if we take MT numbers.

They may well be quite bulky, but the ability to use an ordinary power plant instead of a jump drive type power plant plus fuel tankage taking up 50% of ship's volume makes a huge difference in performance.

What I try in this thread is how to explain the huge amounts of fuel needed by JD (according to canon), for we have calculated only a mere 1% (or 0.333...%) must be burned.

My suggestion redux: Some is used for fuel. A little bit is used for cooling. Most of it is used to "soften up" jumpspace to allow a ship to cross the dimmensional interface without getting flattened. At tech levels above Imperial max[*] it becomes possible to enter jumpspace without softening it up first[**].

[*] What I call hyper-tech. Technology that we don't have on Real Life Earth but do have in the Imperium I refer to as ultra-tech.

[**] The last bit added after seeing Robert's recent post.​

Hans

 

[McPerth]

The ones from the Annic Nova? A minmum of six weeks, since it's possible to charge them over six weeks. By inference, at least long enough to perform one jump and get some useful me time in the next system before jumping out again (A full charge can power a jump by each of the AN's two jump drives; this wouldn't be useful if the charge didn't last long enough to perform the second jump).


They may well be quite bulky, but the ability to use an ordinary power plant instead of a jump drive type power plant plus fuel tankage taking up 50% of ship's volume makes a huge difference in performance.


My suggestion redux: Some is used for fuel. A little bit is used for cooling. Most of it is used to "soften up" jumpspace to allow a ship to cross the dimmensional interface without getting flattened. At tech levels above Imperial max[it becomes possible to enter jumpspace without softening it up first.


Hans

True, the ones of AN whould last at least several weeks, but how bulky are they?

As descripted, AN is 600 dton, Jump drives + staterooms + turrets + computer + pinnaces + cargo sum 357 dton, so there are 243 dton unaccounted for. Solar pannels and capacitors?

About the use of hydrogen for "soften up" jumpspace, that isn't how AN works, as she doesn't use it.

About AN being ultra-hi tech, I agree with the entries on this thread that think if it was, empire whould not allow it to register for a salvage fee of kCr 100, but whould confiscate it and pay the players whatever it feels is the finder's reward (go to the Imperial Court if you disagree about the amount payed - tells you a battledress equiped marine... ).

PS: I guess when you say Robert you're talking about Robject. I've been in the forum for just over a month and I don't know the people yet.

 

[Dragoner]

Why is it cheaper/better/faster to use jump fuel?

And if we could make the answer plausable then even better

Best regards,

Ewan

This one is simple, engineering and economics. You did the benefit side of the equation, not the cost. If the AN caps cost 3x what is being used now and only are 2x more efficient, their cost outweighs their efficiency, esp when looking at the economy of scale of the 3I (when manufacturing, distribution and training would be a huge expense). As per economics, the 3I is mercantilist, so any change to the economic model would be fought by powerful forces that control that market now.

I don't think reverse osmotic filter whould suffice. You can produce drinkable water from salt water with those filters, but not destilled water, that is what you need if you want to avoid corrosion and precipitates.

It is thousands of years in the future, so with more efficient filters or multiple, I could see it working. Though the paradigm seems to be you submerge and just open your tanks, so any contaminant is already in the system. Cooling of course you generally have additives, so coolant would be separate from fuel or other uses.

 

[HG_B]

Though the paradigm seems to be you submerge and just open your tanks, so any contaminant is already in the system.

At that TL one assumes multi stage filters. One at the "opening" to filter out any solids & organics, etc. Probably a field effect to kill ANYTHING living also. The difference between TL 3 and present (TL 7) at least... Consider it.

 

[Dragoner]

At that TL one assumes multi stage filters. One at the "opening" to filter out any solids & organics, etc. Probably a field effect to kill ANYTHING living also. The difference between TL 3 and present (TL 7) at least... Consider it.

Yes, but it is hard to tell what might be a contaminant or even "life" when one is talking literally hundreds or even thousands of worlds. Oceans are the cradle of life; to me, there would have to be some analytical protocol where the ocean (and even the world itself) would be subject to examination before refueling.

 

[HG_B]

Yes, but it is hard to tell what might be a contaminant or even "life" when one is talking literally hundreds or even thousands of worlds.

You don't analyse bit by bit. You simply extinguish. Scorched earth style. And yes, by then, they know what constitutes life on thousands & thousands of worlds.

 

[Dragoner]

You don't analyse bit by bit. You simply extinguish. Scorched earth style. And yes, by then, they know what constitutes life on thousands & thousands of worlds.

You extinguish all life on the planet before refueling? :devil:

Just kidding.

Considering we are still discovering new life on this planet, I would question how much they would know about thousands of other planets, many of them with little or only a precursory exam.

Discovering a new alien lifeform in your fuel tanks might not be such a wonderful discovery.