Coleman wonder turbine gives 3x the Betz limit!

4 Responses to Coleman wonder turbine gives 3x the Betz limit!

1. Roger Brown says:

   17/05/2012 at 10:18

   Hi Hugh –

   How can anything beat the Betz limit though? My understanding Betz is a idealized theoretical max based on blades with zero drag.

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   • admin says:

     17/05/2012 at 10:24

     Sorry, Roger, I was being ironic. I quite often see products being touted on the internet with improbable performance claims and, like you, I respect the known laws of physics and treat such claims with mild hilarity.

     Reply
2. Gavin McPherson says:

   11/04/2012 at 19:52

   I think this is a rebranded version of the Sunforce 600W. The manuals are almost identical and Sunforce are listed for technical support.

   Coleman 600W manual
   http://www.homedepot.com/catalog/pdfImages/6c/6c45f8cc-3aae-497d-899f-609195998b6b.pdf

   Sunforce 600W manual
   http://www.sunforceproducts.com/product_details.php?PRODUCT_ID=187

   The Sunforce 600W rotor diameter is 1.31m (giving a Cp of about 0.4) and the Coleman 600W rotor diameter is quoted as 0.65m (giving a magic Cp of about 1.5).

   It looks like Coleman somehow mistook the turbine radius for its diameter. The blades look about 2 foot long to me – see figures 11&12.

   A purchaser might not be disappointed by the turbine’s output, though they may be a little surprised by its size!

   Gavin

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   • admin says:

     11/04/2012 at 20:02

     Thanks, Gavin, I think you have the answer. Although I am still skeptical even after the performance has been divided by four. Still it is physically possible now.
     hugh

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