Falcon... almost... Lands on Barge after boosting Dragon into orbit

Discussion in 'General Science & Technology' started by Yazata, Jan 10, 2015.

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  1. Kittamaru

    Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    *tilt* But... I thought the only major difference between the two was the return of fluid to the reservoir (open loop) vs not (closed loop)? Closed loop has a second pump (charge pump) in addition to the control pump.

    From what I can tell, an open loop shouldn't make it easier to lose pressure entirely (unless the pump failed?), should it?
     
    Kittamaru, Jan 29, 2015
    #21

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  3. billvon

    billvon Valued Senior Member

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    Hydraulic systems often have an accumulator - a pressurized vessel that maintains pressure in the hydraulic system somehow (compressed gas in the top, a spring loaded piston etc.) In "normal" systems it smooths out oscillations from the pump and allows the pump to run only periodically. In a very simple hydraulic system you can get rid of the pump altogether and just use a single pressurized accumulator. The hydraulic fluid is used, then vented or put in an empty tank. When you run out of fluid, you run out of power.
     
    billvon, Jan 29, 2015
    #22

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  5. Kittamaru

    Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    Huh... having a pressure vessel to smooth out oscillations makes sense, given I would imagine even the smoothest of hydraulic pumps have a chattering effect as the gearing or blades completes each "compression" cycle). I wasn't aware that systems were used without an accumulator pump.

    I'm curious - wouldn't it be possible for a system to be setup where the accumulator pump re-pressurizes the pressure vessel? If it runs primarily when there is no hydraulic activity going on, it would eliminate the oscillations in the system, wouldn't it? Though, I guess that would add weight, complexity, and another possible point of failure...
     
    Kittamaru, Jan 29, 2015
    #23

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  7. Billy T

    Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Musk's new video, showing how world's largest lift rocket will be recovered:
     
    Billy T, Feb 1, 2015
    #24
  8. Kittamaru

    Kittamaru Ashes to ashes, dust to dust. Adieu, Sciforums. Valued Senior Member

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    Not gonna lie... that was pretty epic!

    I've not had a chance to really follow SpaceX too much - if I'm not mistaken, each segment is nine-engines... so that makes the HeavyX a 27 engine lift vehicle 0O holy crap

    Being virtually entirely reusable would be a huge cost savings in the end, I'm sure!
     
    Kittamaru, Feb 5, 2015
    #25
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