Modified Fluid 3 (MF3)

The third modification varies the viscosity parameter $\mu$ spatially over the image.  We expand (4), ignoring p, to give the PDE for the variable viscosity fluid model:

$$(\nabla \mu \cdot \nabla) \vec{v} + \frac{\partial \mu }{\par... ... + \mu \nabla \left( \nabla \cdot \vec{v}\right) + \vec{f} = 0$$ (5)

Since the partial differential operator now varies over the image, a fast solution by a basis function expansion or by convolution with filters derived from its Green's functions [10] is no longer possible; instead we use the successive over-relaxation (SOR) iterative method [11].