Quenching boiling in subcooled liquid nitrogen for solidification of aqueous materials

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2000-11, Vol.292 (2), p.169-172
• Main Authors: Hua, T.C, Xu, J.J
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; General aspects; General theory and mathematical aspects; Instrumentation. Materials. Reagents. Research laboratory organization; Quenching boiling; Rapid cooling; Solidification; Subcooled liquid nitrogen
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/S0921-5093(00)01004-2

Rapid cooling is of great importance in solidification of aqueous materials, such as in vitrification of biological cells and tissues, and in quick freezing of food. Quenching of samples into liquid nitrogen is a typical technique to obtain high cooling rate. This paper investigates the quenching boiling of small spheres and a circular plate into saturated and subcooled liquid nitrogen. Effects of the diameters of spheres, the inclination angles of the plate, and the subcooling of liquid nitrogen on quenching boiling are investigated systematically. Boiling characteristics of the small spheres (representing small samples) and the circular plate (representing large samples) are very different from each other. The scale effect of small samples and the inclination effect of large plate on heat transfer performance are obvious. The subcooling of liquid nitrogen can enhance the heat fluxes in all cases, especially in the cases of small samples.