Study of double-diffusive velocity during the solidification process using particle image velocimetry

Abstract

This paper reports the velocity distribution of double-diffusive convection of a binary mixture in a rectangular enclosure during the solidification process. The mixture was a NH 4Cl–H 2O solution. The advanced technique, particle image velocimetry (PIV), was used to measure the velocity distribution in the liquid region during solidification. For the purpose of comparison, the solidification of pure water was studied with the same technique. The temperature of the cooling walls in the test chamber and the temperature of the test solution during solidification were also measured. The double-diffusive flow was found to be stronger at the beginning of solidification; the flow decays as solidification proceeds. The velocity distribution of the hypereutectic solution of NH 4Cl–H 2O has evident difference in comparison with hypoeutectic solution.