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    Flyball spin up time

    For anyone who is familiar with the centrifugal governor of steam engines. I was wondering if the spin up time for the fly balls is faster or easier as compared to whether the balls are permanently fixed at full extension. The question is related to using flyballs like a flywheel energy storage. There would be no spring tension on flyballs, just the balls on arms attaching it to axle. Would it be slightly easier to get the flyballs up to a specific rpm as compared to if they were extended. Hopefully my question is clear enough.

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    Re: Flyball spin up time

    I have not worked around steam engines nor flyball governors. Textbooks tell me the flyballs are normally intended to move up or down in a middle range.
    Gravity has to do with reaching a position where the flyballs are at an equilibrium state. They raise and lower a valve inside a central column, which regulates engine speed.
    If engine speed ever becomes fast enough to make them extend horizontally, then they are no longer regulating the internal valve.


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    Re: Flyball spin up time

    Quote Originally Posted by BradtheRad View Post
    I have not worked around steam engines nor flyball governors. Textbooks tell me the flyballs are normally intended to move up or down in a middle range.
    Gravity has to do with reaching a position where the flyballs are at an equilibrium state. They raise and lower a valve inside a central column, which regulates engine speed.
    If engine speed ever becomes fast enough to make them extend horizontally, then they are no longer regulating the internal valve.
    Thanks, but in this case it is not being used as a governor. Since energy stored in a flywheel is about mass , diameter and rpm it's stands to reason the faster you can increase the rpm of the flywheel the more efficient it would be. Could you accelerate the flyball apparatus quicker or less energy input than a fixed flyball. My thinking is that the flyballs at rest( hanging straight down) would be a smaller radius and therefore would take less torque to rotate. Therefore it should accelerate quicker. As the rpm increased the balls would move outward increasing its radius. But I'm not sure if overall it accelerate to say 1000 rpm faster than if the balls were fixed at full extension.



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    Re: Flyball spin up time

    With moveable arms, the moment of inertia is variable. Lets the flyball spin up faster in the beginning but it slows down when the arms move outwards. At the end, the total rotational energy is the same. Conservation of energy law rules.

    It's a kind of inverse pirouette effect.


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