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Slow Speed Turbine

  1. Apr 14, 2014 #1
    Is there such a thing (other than wind) as a slow speed turbine? If not is it an efficiency issue or what? Turbines seem to be able to put out high horsepower but at a cost of speed. By that I mean its too fast to get useable torque at low speeds. With gas being the source of power and not a fluid like water what do you think it would take to build more torque at low speeds.

    Lets use a boat engine as an example since its load is more constant. If you built a series of turbines but fed them from the edges instead of head on could it be a efficient power source? I assume its either not or not as cost effective as a piston engine but I always tend to wonder about things.

    So what do yall think to get things started?
     
  2. jcsd
  3. Apr 14, 2014 #2

    berkeman

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    Staff: Mentor

    Something like a Low Head Water Turbine?

    https://www.google.com/search?hl=en...=50000...0...1.1.41.img..1.13.956.WljwKIXxZNs


    EDIT -- oops, it looks like you were asking about turbines for engines, not for power generation...
     
    Last edited: Apr 14, 2014
  4. Apr 14, 2014 #3

    cjl

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    The turbines used in the Chrysler Turbine Car were fairly high torque. It's really just a matter of how you set up the turbine geometry (and how you pull the power off of the engine). Most turbine engines spin fairly quickly because the compressor is more efficient at fairly high spin speeds. If you run the power takeoff on a completely separate shaft from the compressor drive turbine though, there's no reason why the two can't be run at dramatically different speeds (allowing for a relatively low speed, high torque power takeoff turbine, and a high speed turbine to drive the compressor).

    http://en.wikipedia.org/wiki/Chrysler_turbine_engines#A831
     
  5. Apr 15, 2014 #4
    Yea I see what you mean about separating the two sections but wouldn't that be wasting some of the compression if you let some blow by to slow the second power takeoff section? I guess you may could have a smaller compressor and let the air expand to be used by a larger turbine so it would turn slower. If im getting it right in my head it would be like having a small fan that puts out a certain CFM at a fast rpm while a larger fan can put out the same CFM but turns slower. The velocity would be different but they are still moving the same amount of air. Does that sound right?

    berkeman: No problem. Sometimes mistakes can lead to new ideas so the info is still welcome.
     
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