Marangoni convection

Marangoni convection is fluid motion driven by gradients in surface tension rather than by buoyancy. When a fluid surface has non-uniform temperature or composition, regions of higher surface tension pull fluid from regions of lower surface tension, generating flow patterns that can rival or exceed buoyancy-driven convection in thin layers.

The effect is named after the Italian physicist Carlo Marangoni, who studied it in the 1860s. It is particularly important in:

• Microgravity environments, where buoyancy is negligible
• Very thin fluid films, where surface-area-to-volume ratios are large
• Crystal growth and semiconductor manufacturing
• The formation of wine tears (the tears