python_codes.linear_theory.Ay

Ay(alpha, A0)

Calculate the hydrodynamic coefficient \(\mathcal{A}_{y}\) using the geometrical model:

\[\mathcal{A}_{y} = 0.5\mathcal{A}_{0}\cos\alpha\sin\alpha.\]

Parameters

• alpha (array, scalar) – Dune orientation with respect to the perpendicular to the flow direction (in degree).

• A0 (array, scalar) – value of the hydrodynamic coefficient for \(\alpha = 0\), i.e. for a dune orientation perpendicular to the flow direction.

Returns

the hydrodynamic coefficient.

Return type

array, scalar