Took the weans a walk away up the back of The Three Towns in Ayrshire where they are installing these big bad boys.

  • GreyShack@lemmy.world
    link
    fedilink
    English
    arrow-up
    42
    ·
    1 year ago

    They disrupt the trailing edge eddies - which is what causes any noise - and so make them quieter. They are often fitted in areas where sound might be a particular issue.

    • kev@mcr.town
      link
      fedilink
      English
      arrow-up
      12
      ·
      1 year ago

      I can’t hear the word eddies without thinking Hitchhiker’s Guide

      “Eddies,” said Ford, “in the space-time continuum.”

      “Ah,” nodded Arthur, “is he. Is he.”

    • Finnbot@lemmy.worldOP
      link
      fedilink
      English
      arrow-up
      2
      ·
      1 year ago

      They are surrounding a farm with hunners of cows in multiple fields, so I wonder if the noise is quite scary for them, hence efforts to make them quieter. Or the farmer insisting. Are they usually quite loud?

    • Trail@kbin.social
      link
      fedilink
      arrow-up
      2
      ·
      1 year ago

      So why don’t my CPU/case fans have serrated edges as well? Because they are too small?

    • Gormolius@lemmy.one
      link
      fedilink
      English
      arrow-up
      2
      arrow-down
      1
      ·
      1 year ago

      Trailing edge you say? So not designed to mince up birds, that’s a relief.

        • GreyShack@lemmy.world
          link
          fedilink
          arrow-up
          8
          ·
          1 year ago

          Most of the bird deaths are not actually physical strikes - it is a result of the massive change of air pressure as the blades pass at speed. Evidently painting one of the blades black - or some contrasting colour - keeps a lot of the birds well away.

            • GreyShack@lemmy.world
              link
              fedilink
              English
              arrow-up
              2
              ·
              1 year ago

              I realise that I had mis-remembered this. It is primarily bat deaths that are caused by the air pressure changes around turbines - not birds. This is because bats have a particularly large and thin lung internal membranes which gives them high efficiency. The rapid decompression in the immediate wake of the turbine blades - particularly towards the tips, which are the fastest moving part of course - damages this membrane.

              Birds have more compact lungs and hollow bones which aid in their breathing - a different solution to the efficiency problem and one that is not as susceptible to these pressure changes.