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Re: [AWES] Yo-Yo Method terms for reel-in phase?

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  • dave santos
    Joe is right that passive is being claimed by some designs in a misleading way for marketing. So is inherent stability (Makani). The mode of semantic abuse
    Message 1 of 8 , Apr 2, 2012
      Joe is right that "passive" is being claimed by some designs in a misleading way for marketing. So is "inherent stability" (Makani). The mode of semantic abuse is to seize on some minor internal passivity or stability, and gloss it as the general description of an otherwise very actively controlled and/or highly unstable AWES design. Its a dead-end ploy, as true inherent stability with passive cycling is such an advantage.
       
      Re: Pumping cycles, Bob is right that "reset" phase is clearer than "cost" phase generally. I use "recovery" phase, after piston cycle usage. There is room for a lot of confusion in describing the many cycles possible in terms of energetic cost. The worst require the grid to give back a lot of power for a slow energetic reset. The best have a quick natural elastic recovery at very low resistance, with enough flywheel momentum in the transmission to output smooth power to the grid. There are endless combinations and variations between the two extremes.
       
      I was an early promoter of the advantages of classic single-line kite "passive" flight control in AWES design (my presentation topic at HAWPCON09) and used "passive" in the same sense that HAWT designers use the term-
       

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      I also commonly use "passive" in the context of self-oscillation of a power wing element by inherent unsteady aerodynamics v. "active" to describe power cycles requiring electromechanical controls (sensors, processors, actuators). Its the same usage for either overall flight control or embedded power modules, with care not to over-generalize.
       
        
    • blturner3
      I think it should be called reel-in phase. You will likely end up with a formal name for each phase of each design and several informal ones. 4 stroke
      Message 2 of 8 , Apr 3, 2012
        I think it should be called "reel-in" phase. You will likely end up with a formal name for each phase of each design and several informal ones.

        4 stroke engine.
        Intake, Compression, Power, exhaust.
        Informal:
        Suck, Squeeze, Bang, Blow. ;)

        Brian


        --- In AirborneWindEnergy@yahoogroups.com, Dave Lang <SeattleDL@...> wrote:
        >
        > "Cost-phase", "Passive-phase", "Reset-phase", etc.......are just words!
        >
        > If you do your simulation/experimentation homework, you will know
        > fairly precisely what the impact of this phase is. Any AWE "Yo-Yo"
        > scheme must address this phase at all levels of design/production
        > assessments. It is only when this phase has been explored no more
        > deeply than in "term-only" and/or in such a way as to obscure actual
        > behavior that semantics become misrepresentative.
        >
        > Ironically, the deceptive obfuscation of this vulnerable aspect of
        > Yo-Yo schemes, is no where near as egregious as the deceptive
        > obfuscation of entire concepts (need not mention projects here ? :-))
        >
        > DaveL
        >
        >
        >
        > At 9:05 AM -0600 4/2/12, Bob Stuart wrote:
        > >
        > >
        > >Perhaps "Reset" phase would convey both meanings for general
        > >discussions. "Cost" is incisive for the engineer doing an analysis,
        > >but not obviously meaningful to the layman.
        > >
        > >Bob Stuart
        > >
        > >On 2-Apr-12, at 8:45 AM, Joe Faust wrote:
        > >
        > >>In the Yo-Yo method, the reel-in phase is a cost phase
        > >>
        > >>where the AWES is active in spending energy;
        > >>such cost phase is far from "passive."
        > >>
        > >>The cost phase takes energy and time. The time used in the cost
        > >>phase is time where energy is not being positively produced.
        > >>
        > >>Some developers are referring to the cost phase or reel-in phase as
        > >>the "passive" phase, which I vote as being misleading.
        > >>
        > >>What say you?
        > >>
        > >
        > >
        >
      • dave santos
        Brian,   Reel-in phase does not apply to all the short-stroke pumping designs that recover or reset by an elastic recovery of a spring and/or lever,
        Message 3 of 8 , Apr 3, 2012
          Brian,
           
          "Reel-in phase" does not apply to all the short-stroke pumping designs that "recover" or "reset" by an elastic recovery of a spring and/or lever, and the like, without reeling. There is "reel" confusion as to what a "yo-yo method" is. In the past it has been applied very loosely, sometimes to opposed alternating kites, sometimes almost like a trademark. If what is meant is only "reel" systems, as Dave Lang defined them in 2004, then "reel-in phase" specifically applies, but there is still potential for confusion with all systems that just use reels for launching and landing, but not for a direct power cycle. Phases called, "retract", "reset", "recovery" and so on, are clearly more universal.
           
          I have reconsidered the "tow" usage issue, and now think "winch-tow" is a proper useful descriptor, as long as no confusion is created by just saying "tow launch", which tends to imply a moving tow vehicle. "Winch launch" is very clear, and "step-tow" is a special case of usually pure winch launch, although a tow vehicle could be used.
           
          We are slowly "writing the book" on proper precise AWE nomenclature. Sorry to all those who despair over such fussiness, but the end result will be great engineering expressiveness with a few choice words,
           
          daveS
           

           
            
        • blturner3
          Yes, I was specifically thinking of systems were the power generation is due to the reeling action. It would not apply well to short-stroke or elastic systems.
          Message 4 of 8 , Apr 3, 2012
            Yes, I was specifically thinking of systems were the power generation is due to the reeling action. It would not apply well to short-stroke or elastic systems.

            Retract seems a good choice for many system concepts. I think that "reset" and "recovery" are a bit too broad for most systems, and their popular usage is often in reseting or recovering from a fault condition. I don't think I have ever heard reset used for a system with just 2 states. I looked up the definition and it mentions returning to zero for most usages.

            An elastic system would be equivalent to a "return" spring.

            Brian



            --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
            >
            > Brian,
            >  
            > "Reel-in phase" does not apply to all the short-stroke pumping designs that "recover" or "reset" by an elastic recovery of a spring and/or lever, and the like, without reeling. There is "reel" confusion as to what a "yo-yo method" is. In the past it has been applied very loosely, sometimes to opposed alternating kites, sometimes almost like a trademark. If what is meant is only "reel" systems, as Dave Lang defined them in 2004, then "reel-in phase" specifically applies, but there is still potential for confusion with all systems that just use reels for launching and landing, but not for a direct power cycle. Phases called, "retract", "reset", "recovery" and so on, are clearly more universal.
            >  
            > I have reconsidered the "tow" usage issue, and now think "winch-tow" is a proper useful descriptor, as long as no confusion is created by just saying "tow launch", which tends to imply a moving tow vehicle. "Winch launch" is very clear, and "step-tow" is a special case of usually pure winch launch, although a tow vehicle could be used.
            >  
            > We are slowly "writing the book" on proper precise AWE nomenclature. Sorry to all those who despair over such fussiness, but the end result will be great engineering expressiveness with a few choice words,
            >  
            > daveS
            >
          • roderickjosephread
            charge discharge, unwind rewind, load unload, lift drop, press release, I guess until the set yoyo devices is defined we won t have a correct description for
            Message 5 of 8 , Apr 4, 2012
              charge discharge, unwind rewind, load unload, lift drop, press release,
              I guess until the set "yoyo devices" is defined we won't have a correct description for the machine specific complementary action involved.
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