Thesis presented January 27, 2012

Abstract:
This research work, performed with the help of the French Atomic Energy Committee and the French Space Agency, tries to bring a new contribution regarding the boiling phenomenon. It deals in particular with the boiling crisis, which corresponds to the departure from nucleate boiling towards film boiling, and tries to underline the governing mechanisms of its trigger. The approach is mainly based on experiments. They are realised with the help of magnetic gravity compensation apparatus which contribute to reproduce in laboratory the microgravity conditions needed to realise the study. Two-phase oxygen and hydrogen placed in near-critical conditions are the study fluids. The technical resources which are available at the Low Temperature Department of CEA Grenoble give a useful help to have the work well done. The purpose is dual: on the one hand, to show that magnetic compensation of gravity is an interesting technique to complete the usual inertial compensation means; on the other hand, to contribute on the critical heat flux basic research.The topics are numerous: showing the advantages and the weaknesses of the magnetic compensation with a deep magnetic field study; designing, manufacturing and assembling experimental cells; qualifying and setting up the experimental apparatus; eventually, performing the model validation experiments.

Keywords:
Microgravity, Magnetic compensation, Hydrogen, Oxygen, Heat transfer, Phase transition

On-line thesis.