In this thesis, the noncoalescence phenomenon of two silicone oil droplets induced by thermocapillary convection is numerically investigated by the finite element method. The Arbitrary Lagrangian-Eulerian and conservative level set methods are used to trace the moving and deforming droplet/air interface. The noncoalescence is attributed to the existence a self-lubricating air film between two droplets to separate them from coming into contact, which is generated by the thermocapillary convection. The effect of temperature difference, interstitial film thickness between the two droplets, and silicone-oil viscosity on the ability of thermocapillary convection in the coalescent suppression is considered.
The numerical results indicate that the thermocapillary convection affects the deformation of the droplet shape. The ability of thermocapillary convection can be enhanced by the increase of the temperature difference or the reduction of the interstitial film thickness and the decrease of the liquid viscosity. The deformation of droplet/air interfaces might also be enlarged with the stronger thermocapillary convection. Moreover, the air velocity swept by the motion of silicone-oil into the lubricating air film would be higher and hence, the coalescencing suppression is improved.

In this thesis, the noncoalescence phenomenon of two silicone oil droplets induced by thermocapillary convection is numerically investigated by the finite element method. The Arbitrary Lagrangian-Eulerian and conservative level set methods are used to trace the moving and deforming droplet/air interface. The noncoalescence is attributed to the existence a self-lubricating air film between two droplets to separate them from coming into contact, which is generated by the thermocapillary convection. The effect of temperature difference, interstitial film thickness between the two droplets, and silicone-oil viscosity on the ability of thermocapillary convection in the coalescent suppression is considered.
The numerical results indicate that the thermocapillary convection affects the deformation of the droplet shape. The ability of thermocapillary convection can be enhanced by the increase of the temperature difference or the reduction of the interstitial film thickness and the decrease of the liquid viscosity. The deformation of droplet/air interfaces might also be enlarged with the stronger thermocapillary convection. Moreover, the air velocity swept by the motion of silicone-oil into the lubricating air film would be higher and hence, the coalescencing suppression is improved.

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