Mitigating Thermal Dissipation in Electromagnetic Centrifuges for High-Throughput Mass Separation

Viscous dissipation and gas heating impose fundamental limits on plasma separation technologies by coupling azimuthal flow and heating mechanisms through the Lorentz force. The equilibrium separation factor for an electromagnetic centrifuge (EMC) is defined as exp(ΔMV²/2kT), leading to a nonlinear tradeoff between driving force and temperature, captured by the parameter V²/T. The minimum value of this parameter for notable enrichment factors depends on the mass difference between species. Systems targeting large mass differences (e.g., rare earth element extraction and waste processing) can tolerate lower V²/T, while small mass difference separations (e.g., hydrogen isotopes in fusion exhaust and uranium isotope enrichment) demand higher values and tighter optimization. We present a simplified model capturing how V²/T scales with device geometry and boundary conditions, and support it with experiments in a partially ionized EMC. The EMC operates at a collisional pressure of ~2.5 Torr relevant to high-throughput industrial adoption, with ≤500 mA current and ~0.15 T magnetic field acting on 3 SCCM argon in a coaxial geometry with variable annular thickness, aspect ratio, and cooling mechanisms. Results reveal key trends linking geometry and operational conditions to separation performance, informing future EMC system design to overcome conventional scaling constraints based on dissipation mechanisms.