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Two Tiny Gas Turbines

Posted by ryuzaki0 on from the burn-a-hole-in-your-pocket dept.

Turbines are in the news this morning. bobtheimpossible writes to point out a BBC article on a Swiss turbine that runs at half a million RPM and generates 100 watts. It's the size of a matchbook. And af_robot alerts us to an even more diminuitive gas turbine on a chip, developed at MIT, that generates 10 watts — plenty for portable electronics — and should run 10 times as long as a battery of comparable weight and cost. A commercial version is 3 to 5 years away.

3 of 202 comments (clear)

  1. Re:Inefficiencies? by Colin+Smith · · Score: 4, Informative

    Sorry, but bollocks it is. A gas turbine is a heat engine, the efficiency is determined by difference between the temperature at combustion and the exhaust gases. 50% would be excellent for a gas turbine.

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  2. Re:Inefficiencies? by jandrese · · Score: 4, Informative
    What's 5% of 100 watts?
    Um, about 5 watts? That's pretty low heat dissipation all told. Exaust and mechanical stress are definatly a concern though, although with components that small at least the masses will be tiny, even if the RPM is exceedingly high. I wonder about the sound though, is it going to drive dogs insane everytime you turn on your Laptop?
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    I read the internet for the articles.
  3. Article close to pure crapola! by Ancient_Hacker · · Score: 4, Informative
    An efficiency of 95% ! ?

    The best large gas turbines do about 35%.

    And efficiency drops very quickly with size-- you see friction goes down as the square of the size, while power goes down as the cube. Somewhere between the size of a sausage and a hot dog, all the turbine power is going into overcoming friction.

    And the biz about 1 million RPM is pure hokum-- the worlds record is a bit below that, and that was with a tungsten alloy rotor in a vacuum chamber.

    Methinks some press agent was drinking while on duty.