Near-critical fluids under microgravity: Highlights and perspectives for Europe

Started more than 15 years ago, the investigation of fluids and liquid mixt ures near their gas-liquid or liquid-liquid critical points has led to a nu mber of important findings. We note the determination of critical, universa l power law behavior, for the specific heat and the adsorption properties n ear a solid wall. Also came out a unified view of phase separation, which h as-been later applied to the development of biological patterns. A new, ver y fast, mechanism of heat transport has been discovered that has been coine d "piston effect". This effect has been already applied in the space indust ry. All these findings have been obtained thanks to a good coordination bet ween ESA and CNES (and also with the NASA and USSR - Russian space agencies ). The future of the program is linked to the CNES DECLIC facility and the ESA Fluid Science Laboratory (FSL). DECLIC has been designed to extend the interval of temperature regulation beyond the critical temperature of water (550 K) so as to investigate chemical reactions under conditions of superc ritical water. Thanks to the construction of a special vibrational Experime nt Container for FSL, the thermal and mechanical behavior of fluids under f orced vibration can be investigated.