4. The resistance of the fin

The total resistance of a fin can be split up into several components. These individual components are interacting and the improvement of one factor may be followed by a deterioration of another factor.

The total resistance of a fin is the summation of several types of resistance.

The (a) frictional form resistance is occasioned by the form resistance and the frictional resistance. It is influenced by the following parameters:

  • cross-sectional shape of profile (camber distribution and thickness distribution)
  • sailing speed
  • the flow pattern of the boundary layer
  • roughness of surface

The (b) induced resistance is occasioned by the fin design.It is determined by the lift distribution on the fin and is influenced by the following features:

  • outline
  • aspect ratio
  • taper ratio
  • torsion