When submitted to vertical vibrations for frequencies from 15 to 150 Hz, granular materials show several convective patterns, as symmetric, asymmetric, one single, one pair and multi-pairs of convection rolls. The vibration frequency (f) plays a significant role in the number of rolls and their flow directions, while the vibration acceleration (Г) mainly affects the size of roll and strength of flow. The Г - f phase diagram is presented and divided into the global, local, unstable and non-convection regions. Slope of the granular surface decreases with increase of Г, and the grains at different positions collide with the bottom un-synchronously.
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