Refractive index based optical techniques are helpful tools for the qualitative and quantitative investigation of temperature and concentration profile in the fluid flow. These techniques play an important role in the applications where, the compositional and thermal profiles are continuously evolving in the flow field. The objective of present work is to develop and describe a two-wavelength interferometry technique for the simultaneous measurement of interaction between concentration and temperature distribution in the continuously evolving double diffusive convection field.
Transparent mixtures that allow the light/laser beams to pass through it are the model systems that can be utilized for such optical techniques. Importance of double diffusive convection during unidirectional solidification of binary solutions has been realized in the literature. The present experimental work, conducted using dual wavelength interferometry technique, pertains to the study of the onset and further development of double diffusive layers (DDLs) during unidirectional solidification of aqueous solution of NH₄Cl binary solution.