Congratulation to David Schmid

David investigated the two-phase flow phenomena of flow boiling Carbon Dioxide (CO₂) at the European Organization for Nuclear Research (CERN) in Geneva under the supervision of Prof. Jürg Schiffmann from EPFL and Prof. Rémi REvellin from INSA Lyon. His work was embedded in a research program for the development of new refrigeration technologies with natural refrigerants for future High Energy Physics (HEP) experiments.

Carbon Dioxide (CO₂) is known to have very beneficial thermophysical properties and therefore great potential to provide less detrimental solutions than commonly used synthetic working fluids. Furthermore, its non-toxicity, non-flammability and radiation hardness make it a particularly well suited candidate for the cooling systems of future accelerator and detector components in the underground facilities of CERN. Within the scope of his work, a dedicated test facility has been built in the laboratories of the Experimental Physics department and the Detector Technology group at CERN to better understand the flow boiling phenomena of CO₂. With this unique test facility, pressure drop and heat transfer measurements have been carried out and flow pattern observations have been recorded. In total, a database of more than 3,500 data points has been compiled during the investigations. As a result, his studies provide more accurate prediction models for designing evaporative refrigeration cycles with CO₂ and in general contribute to a better understanding of its flow boiling phenomena.