Thermal force surface tension gradients

The surface tension gradients can be important in very thin liquid layers or in reduced gravity environment (microgravity). For example, a crystal grown from its melt under reduced gravity is governed by convection driven by thermally induced surface tension gradients rather than buoyancy forces. 

The thermal force discussed heretofore can be attributed to externally imposed momentum transport by the gas molecules. Several theories [2.143,144] have been proposed for an additional effect in which surface-tension gradients are set up in droplets of relatively small viscosity by the temperature gradient. The surface-tension gradient produces internal circulation of the drop. This results in motion... 

The hydrodynamic instability leading to convective flow in the biochemical systems is driven by unbalanced forces (surface tension) at the liquid/gas interface, mainly caused by temperature gradients due to evaporative cooling [1,4]. Our experiments show that the chemical composition of the solution has to be accounted for as well. The significant parameters for the onset of pattern formation are the thermal and the solutal Marangoni numbers. Both are also important for spatial patterning in biochemically reactive liquid layers. 

Transport of droplets by thermal capillarity is an actuation concept utilizing thermocapillaiy forces. A temperature gradient across a liquid droplet leads to a difference in surface tensions at both... 

---