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Bosnia and Herzegovina -
Bosnia and Herzegovina -

Bosnia and Herzegovina - "SCIENCE ~ 100 YRS OF TESLA TURBINE" FDC 2013 !

$ 2.37

Availability: 23 in stock
  • Quality: Mint Never Hinged/MNH
  • Modified Item: No
  • Type: First Day Cover
  • Certification: Uncertified
  • Topic: Science
  • Refund will be given as: Money back or replacement (buyer's choice)
  • Return shipping will be paid by: Buyer
  • Restocking Fee: No
  • Grade: VF/XF (Very Fine/Extremely Fine)
  • Cancellation Type: First Day of Issue
  • Year of Issue: 2013
  • Theme: Science & Technology
  • Region: Bosnia and Herzegovina
  • Item must be returned within: 30 Days
  • All returns accepted: Returns Accepted

    Description

    Bosnia and Herzegovina - Republic of Srpska
    “
    100 YEARS OF TESLA TURBINE.
    ”
    First Day Cover !
    Reverse of Cover gives details.
    Tesla turbine is a turbine without blades discovered by Nikola Tesla in 1913. Instead of blades it uses the boundary layer effect between the fluid (gas, liquid, vapor) and multiple peaks of smooth disks. Contiguous parts of the fluid acting on the disc because of viscous (fluid friction) and the attractive force and the fluid layer disc. How the rotor has no blades, or any protrusions, it is very solid.
    Tesla turbine should have a very small gap between the disks, maximum 0.4 mm and the surface should be very smooth. In Tesla's time they could not find such materials for very thin discs, as they distort under load and distorted, so Tesla turbine has not experienced commercial success. Still today examine ways of applying Tesla's turbine, even there since 2010 and construction of the wind farm. The advantage lies in the use of low-power turbines. Tesla's desire was to use a turbine for geothermal power.
    Date of Issue: 29th November 2013.
    (BOS19) ~ Rd Bg 11.