  A liquid in Cassie-Baxter state above a structured superhydrophobic surface
is ideally suited for surface driven transport due to its large free surface
fraction in close contact to a solid. We investigate thermal Marangoni flow
over a superhydrophobic array of fins oriented parallel or perpendicular to an
applied temperature gradient. In the Stokes limit we derive an analytical
expression for the bulk flow velocity above the surface and compare it with
numerical solutions of the Navier-Stokes equation. Even for moderate
temperature gradients comparatively large flow velocities are induced,
suggesting to utilize this principle for microfluidic pumping.
