The DARPA 100 Year Starship

Discussion in 'Science and Technology' started by John O., Jun 18, 2011.

  1. Scroogourner

    Scroogourner Admiral Admiral

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    Heck, stop the trains for a week and see what happens.
     
  2. MANT!

    MANT! Rear Admiral Rear Admiral

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    California has had many budget issues over the years, until the budget is passed, many state workers (including law enforcement) were provided with I.O.U.s instead of actual paychecks..some banks didn't honor the IOUs..so those workers effectively didn't get paid... Yet, the system didn't collapse..and riots didn't happen..folks just protested and told the elected representatives to do their jobs...


    The infrastructure isn't as "fragile" as folks think it is...

    without a natural disaster to eliminate governmental control, the system works very well...
     
  3. Scroogourner

    Scroogourner Admiral Admiral

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    ^Stop the trains for a week and people starve.
     
  4. MANT!

    MANT! Rear Admiral Rear Admiral

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    NOT unless you can stop the trucks...
     
  5. Scroogourner

    Scroogourner Admiral Admiral

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    The trains feed the distribution centers where the trucks load up.
     
  6. MANT!

    MANT! Rear Admiral Rear Admiral

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    Brazil has no freight trains..it does alright..it wouldn't be much of a stretch to redo the distribution network to do trucks..after all the trucks can go to where the trains load up..and drive to those same distribution centers.. maybe a week for the government to do it..and prices would increase..but certainly not enough to bring civilization down..
     
  7. Scroogourner

    Scroogourner Admiral Admiral

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    So comparing a nation that has never used trains for distribution to one that looses the trains it uses massively for distribution? Yep, that's a fair comparison. There aren't enough trucks in the U.S. to move the volume. People would start to starve in that week. Look what happened with New Orleans. Imagine if New York went without food for a week. Civilization might not end, but it would be one hell of a disaster. Ever hear the saying "Every society is 3 meals away from revolution"?
     
  8. John O.

    John O. Rear Admiral Rear Admiral

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    Ordinary people all over South Texas during Ike, Rita and Katrina went without 3+ regular meals and didn't revolt because the average American has more integrity than the common looter. I was down there for part of it and I knew plenty of ppl who kept their shit together.
     
  9. John O.

    John O. Rear Admiral Rear Admiral

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    Bump.

    This conference is coming up in about a week, just putting the final touches on my presentation. The paper's already been submitted and accepted. When publication rolls around in a few months I'll see if I can upload/attach a copy into this thread.

    Incidentally I have better data now for the 'sweet spot' ideal operating condition. I'm not sure how much I kept this thread apprised of how my concept design changed but it advanced into a new variation of potential fusion propulsion. We call it the "Viper Pulsed Fusion Rocket". Viper evolved as an inside joke attempt to meld together "PFR" and "HIIPER" into "PFHIIPER" (Viper). I'm gonna summarize extremely briefly and you guys can read the paper later if you want. We feed a helicon plasma into an IEC, get fusion through some breakthrough technologies (some of which have been invented, 1 or 2 haven't), we get power production (~140 MW), and thrust by magnetically collimating the alpha particles that come out of the reaction, putting them through a direct energy conversions cycle to syphon off enough power to run the system (~24 MW IIRC), and then comes the interesting part. People have theorized about something called "Diluted Fusion Product" propulsion whereby you essentially convert the "nuclear thermal rocket" idea of a fission reactor into a fusion reactor. We take the alpha particles which are extremely energetic, and mix them with a neutral gas like hydrogen, in a magnetically confined chamber, and exhaust the mix. Assuming various efficiencies (many allowing for significant losses), we get pretty good numbers:

    Thrust: 660 N
    ISP: 30 million

    Operating off-optimal you can actually get thrust up to about 3 kN and it only brings your ISP down to.... idk, 1-3 million I think. Pretty awesome.

    On a 2-month low thrust transfer to Mars, with about 1000 kg of propellant, the engine could pull about 460 MT of cargo. Beast eh?
     
    Last edited: Sep 23, 2011
  10. stonester1

    stonester1 Rear Admiral Rear Admiral

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    Amazing...
     
  11. John O.

    John O. Rear Admiral Rear Admiral

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    Thought you guys might enjoy this... line art schematic of the Viper engine I designed.

    [​IMG]
     
  12. RAMA

    RAMA Admiral Admiral

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    Cool, Hope to hear more of this soon.
     
  13. John O.

    John O. Rear Admiral Rear Admiral

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    Typo earlier, btw - ISP - 300k, not 30m.
     
  14. publiusr

    publiusr Rear Admiral Rear Admiral

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    Pretty nice. I keep hoping we we see a Nuclear Salt Water rocket one day--but how to deal with the heat...