Energy transformation mediated by electromagnetically-driven instabilities - from astrophysics to industrial applications – MagnetDrive

The conversion of electromagnetic energy into kinetic energy by an electrically conducting fluid is a ubiquitous phenomenon that can be found in several natural systems as well as industrial applications.
In nature, the accretion of matter around black holes and proto-stars is a typical example in which a tremendous amount of kinetic energy is produced from strong magnetic fields. Similarly, many industrial systems involve a liquid metal subject to electrical currents or external magnetic fields, among which we can cite electromagnetic driving of liquid sodium or production of aluminum by electrolysis.
Despite the importance of these applications, several aspects of the dynamics of electromagnetically driven (EMD) flows still remain poorly understood. One major problem is to identify the mechanisms that limit the maximum efficiency of magnetic to kinetic energy transformation in the presence of turbulence. Interestingly, this bound on the efficiency almost always results from unexpected flow instabilities occurring as soon as the size of the system or the magnitude of the driving becomes large enough. The origin itself of such flow instabilities is not fully understood.

The aim of this research project is twofold: first, we want to elucidate some of these major aspects through original laboratory MHD experiments, connected by a simple question: why, how and under which circumstances do instabilities mediate energy conversion in electromagnetically-driven flows? We therefore aim at coordinating theoretical, numerical and experimental efforts to identify general mechanisms involved in such instabilities and substantially expand our comprehension of the dynamics of electromagnetically driven flows
Second, this project strongly connects to industrial and astrophysical applications, such as interstellar turbulence and liquid metal batteries. One purpose of the project is precisely to bridge the gap between fundamental physics and industrial motivations. To complete these tasks successfully, our work program is divided into two different parts with their own interests and purposes, but strongly connected through the general questions raised above.