Thermal Marangoni Effect

Marangoni effect Thermal Marangoni effect Thermocapillary effect... 

All of these disturbances cause a many-fold increase in the rate of transfer of solute across the interface. If a chemical or thermal difference along an interface causes an interfacial tension gradient, violent flow in the direction of low a will result. This action is usually termed the Marangoni effect. 

We then go on to consider three examples of instabilities that arise because of buoyancy and Marangoni effects in a nonisothermal system. This is preceded by a brief discussion of the Bousinesq approximation of the Navier Stokes and thermal energy equations. 

In view of the term (jJl in Eq. (9), the Marangoni effects are hidden in the left-hand side of the interfacial momentum balance equation (8) through the surface gradients of (Ja. The thermodynamic surface tension, dJa, depends on the adsorption and temperature. The derivatives of with respect to In and InT define the Gibbs elasticity for the i-th surfactant species, Et, and the thermal analogue of the Gibbs elasticity, Ef. 

Thermocapillary effect Marangoni effect Thermal Ma-rangoni effect... 

Figure 3.3. Various features of diffusion and convection associated with crystal growth in solution (a) in a beaker and (b) around a crystal. The crystal is denoted by the shaded area. Shown are the diffusion boundary layer (db) the bulk diffusion (D) the convection due to thermal or gravity difference (T) Marangoni convection (M) buoyancy-driven convection (B) laminar flow, turbulent flow (F) Berg effect (be) smooth interface (S) rough interface (R) growth unit (g). The attachment and detachment of the solute (solid line) and the solvent (open line) are illustrated in (b).

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