Unsteady BEM Settings

The theory of the unsteady polar BEM is briefly described in Polar Grid.

Unsteady BEM Parameters

  • Azimuthal Polar Grid Discretization: The polar grid is discretized into the chosen number of azimuthal sections. A value of 1 is equal to the BEM without a polar grid.

  • Include Tip Loss: This activates the classical BEM tip loss correction to account for a finite number of blades, see Glauert1.

  • Convergence Acceleration Time: The time lag constants in the unsteady BEM implementation are increased by a factor of 20 during the time span entered by the user. This enables a much faster convergence of the unsteady BEM towards a steady operational point.

1

H. Glauert. Airplane Propellers, chapter Aerodynamic Theory, pages 169–360. Springer Berlin Heidelberg, 1935. doi:10.1007/978-3-642-91487-4_3.