  Particle image velocimetry is applied to the lid-driven flow in a cube to
validate the numerical prediction of steady - oscillatory transition at lower
than ever observed Reynolds number. Experimental results agree with the
numerical simulation demonstrating large amplitude oscillatory motion
overlaying the base quasi-two-dimensional flow in the mid-plane. A good
agreement in the values of critical Reynolds number and frequency of the
appearing oscillations, as well as similar spatial distributions of the
oscillations amplitude are obtained.
