CouplingStress:

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   Calculates the stress acting on coupling.
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   Form:
   [sigma , tau] = CouplingStress ( d )
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   ------
   Inputs
   ------
   d          (1,1)  Data structure
                     .OD         (1,1)  Outer diameter (m)
                     .ID         (1,1)  Bore Diameter (m)
                     .v          (1,1)  Speed (m/s)
                     .t          (1,1)  Chord (m)

   -------
   Outputs
   -------
   sigma      (1,1)  Axial Stress (Pa)
   tau        (1,1)  Shear Stress (Pa)

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   Reference: 

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