Nonlinear Laser-induced Deformations and Forces at Liquid-Liquid Interfaces near the critical Point.

• Main Author: Aanensen, Nina Sasaki
• Format: Others
• Language: English
• Published: Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk 2011
• Subjects: ntnudaim:6592; MTFYMA fysikk og matematikk; Teknisk fysikk
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14264

The theory of laser-induced liquid-liquid interface deformation has been presented and used to derive a differential equation describing the shape of the deformation. The differential equation has been investigated and solved numerically, and the results have been compared to the experimental results of the Bordeaux group. A model describing the maximum depth of the deformation based on the theory of a sphere in an electric field has also been investigated.The deformations from the numerical solutions of the differential equation are too wide compared to the experimental results. The shoulder-shape that has been observed in the experiments is not present in the numerical solutions. There is reason to believe that the differential equation may be too simple in order to describe the liquid-liquid interface deformation for nonlinear cases. There may be thermal effects that changes the liquid properties due to local temperature variations induced by the laser, causing the liquid parameters to change along the deformation.The model used to estimate the deformation depth does not give reasonable results, as it leads to a deformation that is more than 100 times larger than what is observed in the corresponding experiments. The assumptions made for this model may not be valid, and a discussion on what should be done in order to improve the model is included in this text.