34.6.2 am_cosine

One sub-option for varhmix is option am_cosine which applies a cosine function to the constant value of am to counteract the convergence of meridians. When implemented with the option  laplacian_velocity, the Laplacian viscosity is given by

$$A_{l} = am \cdot csuj.$$ (34.73)

When implemented with option biharmonic_velocity, the biharmonic viscosity is given by

$$A_{b} = ambi \cdot (csuj)^{3}.$$ (34.74)