Homepage Forums National Ignition Facility (NIF) et al NIF upgraded for summer campaign

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  • #1359
    AvatarIvy Matt
    Participant

    NIF released their April update halfway through May this month. Usually they’ve been very punctual. I thought the following quote of note:

    A NIF Facility Maintenance and Reconfiguration period began on April 25 and was scheduled to continue until May 15. The NIF team’s goal is to upgrade NIF’s peak power to 500 trillion watts in preparation for this summer’s experiments.

    #11945
    Avatarikanreed
    Member

    Ivy Matt wrote: NIF released their April update halfway through May this month. Usually they’ve been very punctual. I thought the following quote of note:

    A NIF Facility Maintenance and Reconfiguration period began on April 25 and was scheduled to continue until May 15. The NIF team’s goal is to upgrade NIF’s peak power to 500 trillion watts in preparation for this summer’s experiments.

    That’s insane. The Hiroshima bomb was in the neighborhood of 60 trillion joules of energy. They’d pass that in an eighth of a second. I don’t pretend that’s even near how long they’re firing, but that’s still an unimaginable amount of power.

    #11947
    AvatarJoeviocoe
    Member

    ikanreed wrote:

    NIF released their April update halfway through May this month. Usually they’ve been very punctual. I thought the following quote of note:

    A NIF Facility Maintenance and Reconfiguration period began on April 25 and was scheduled to continue until May 15. The NIF team’s goal is to upgrade NIF’s peak power to 500 trillion watts in preparation for this summer’s experiments.

    That’s insane. The Hiroshima bomb was in the neighborhood of 60 trillion joules of energy. They’d pass that in an eighth of a second. I don’t pretend that’s even near how long they’re firing, but that’s still an unimaginable amount of power.

    No, that was 500 Trillion WATTS not JOULES. The highest NIF has gotten I believe was 1.8 Megajoules per shot. Maybe a bit higher.

    #11954
    Avatarannodomini2
    Participant

    Their largest shot was 1.694 Mj with 370TW of laser power, so iro 4.5ns.

    At 500TW, so it would 2.289Mj for the same duration.

    #11957
    Avatardennisp
    Member

    Joe I think ikanreed knows the difference. His point is that if they were able to maintain that power output for 1/8 second, it would be the the same energy as Hiroshima. They actually maintain it for a much shorter span of time, but the comparison still gives a good impression of the power level they’re talking about.

    #11958
    AvatarJoeviocoe
    Member

    dennisp wrote: Joe I think ikanreed knows the difference. His point is that if they were able to maintain that power output for 1/8 second, it would be the the same energy as Hiroshima. They actually maintain it for a much shorter span of time, but the comparison still gives a good impression of the power level they’re talking about.

    I am not a fan of that comparison. It is misleading more than “a good impression”.

    Here’s a better impression. Hiroshima bomb was 60 trillion joules, NIF shot was 2 million joules. That is a difference of 30 million times! There is no “maintaining” for anywhere near a second.

    Comparing pulse power machines that operate at infinitesimal smaller pulses than a “second”… to a constant power device that would and could run for seconds minutes and/or days… is, well, nonsense.

    There is no lower limit to time. It gets smaller and smaller. The reason why I think that comparison is misleading, is because it plays on some people’s inability to comprehend things too large or too small. We perceive the World of the medium. – Alan Watts.

    The fallacy:
    “So the NIF Laser fires in a couple of nano seconds, that is small. 1/8th of a second is small too. They must be comparable”. The difference between 4.5 nanoseconds and 1/8 of a second … is the same difference between 1 second, and about a year.

    Even if you wanted to, and the Lasers could sustain several minutes of 500 trillion watts…, the entire NIF facility, could not hold that much energy in all of their storage systems. They would literally need about 15 Thousand Tons of TNT to store that energy chemically. Or an actual mass of nuclear material (in which case would be an exact comparison).

    #11959
    AvatarJoeviocoe
    Member

    dennisp wrote: Joe I think ikanreed knows the difference. His point is that if they were able to maintain that power output for 1/8 second, it would be the the same energy as Hiroshima. They actually maintain it for a much shorter span of time, but the comparison still gives a good impression of the power level they’re talking about.

    Sorry if that came across as a bit harsh. The reason I am so adamant about not comparing things like that, is because it can foster unscientific reasoning.

    And more importantly, newcomers or any less educated folks in politics or the media… could think that this facility contains that much energy at any given time.. and a simple accident (like the beam not shutting off for 1/8th of a second) could vaporize the city of Livermore, California.

    BTW, 2 Megajoules is about 0.55 kilowatt-hours. About half the energy in your standard 12 volt Car Battery. I wouldn’t want anyone comparing that to an Atomic Bomb.

    #11960

    Only a hundred car batteries per NIF shot (in the pulse power). That is better than I expected when you put it those terms. Z is 22 MJ is 6 batteries per shot. I personally prefer the apple pie energy system at ~1 MJ/slice or 6-8 MJ per pie. Some call it pulse power; I call it dessert. 🙂

    #11961
    Avatardennisp
    Member

    Joeviocoe wrote: could think that this facility contains that much energy at any given time.. and a simple accident (like the beam not shutting off for 1/8th of a second) could vaporize the city

    Ok that’s a good point.

    #11962
    Avatarvansig
    Member

    no, it’s silly. what could keep that beam running for 1/8th of a second? nothing could

    #11963
    Avatarzapkitty
    Member

    vansig wrote: no, it’s silly. what could keep that beam running for 1/8th of a second? nothing could

    People can be silly, on occasion, and it’s sometimes hard to predict exactly what they’ll choose to be silly about…

    #11964
    AvatarLerner
    Participant

    Wow, that’s a great comparison, assymetric! So we could measure FF-1 in pistachio-nut caloric equivalent. At full power each shot uses five pistachios–right now we are running with 2 and a half. So 5MW is only 250 nuts/second–it does not seem like much that way.

    #11966

    Someone told me that it was common to use apple pie and other common familiar foods to explain power generation back in the 1970’s. It probably meant a bit more back then since everyone loved the calorie unit for energy.

    #12010
    AvatarIvy Matt
    Participant

    The May update is now online. Not a whole lot of news, except that the maintenance and configuration was completed on May 18. Presumably NIF is able to operate at 500 trillion watts now, and the summer campaign has begun.

    #12052
    AvatarIvy Matt
    Participant

    June update.

    Might as well add this article too.

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