  The proposed flow in a 3-D cubic cavity is driven by its parallel walls
moving in perpendicular directions to create a genuinely three-dimensional
highly separated vortical flow yet having simple single-block cubical geometry
of computational domain. The elevated level of helicity is caused by motion of
a wall in the direction of axis of primary vortex created by a parallel wall.
The velocity vector field is obtained numerically by using second-order upwind
scheme and 200^3 grid. Helicity, magnitude of normalized helicity and kinematic
vorticity number are evaluated for Reynolds numbers ranging from 100 to 1000.
Formation of two primary vortices with their axis oriented perpendicularly and
patterns of secondary vortices are discussed. Computational results are
compared to the well-known 3-D recirculating cavity flow case where the lid
moves in the direction parallel to the cavity side walls. Also results are
compared to the diagonally top-driven cavity and to cavity flow driven by
moving top and side walls. The streamlines for the proposed flow show that the
particles emerging from top and bottom of cavity do mix well. Quantitative
evaluation of mixing of two fluids in the proposed cavity flow confirms that
the mixing occurs faster than in the benchmark case.
