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How does a reversed-field pinch differ from a tokamak?
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fusion reactor
A tokamak is a device used in nuclear-fusion research for magnetic confinement of plasma.
The reversed-field pinch (RFP) and the tokamak are both toroidal magnetic confinement systems used in nuclear fusion research, but they differ significantly in their magnetic field configurations and engineering requirements.12
The primary distinctions include:
- Magnetic Field Strength: The tokamak operates with a strong toroidal magnetic field, whereas the RFP operates with a weak toroidal magnetic field.1
- Field Line Topology: In a tokamak, the magnetic field lines wind loosely around the torus, creating a weak helical pitch. In contrast, RFP field lines wrap much more tightly, circling the poloidal direction many times before completing a single loop around the torus.2
- Engineering and Design: Because of its weak toroidal field, the RFP design allows for a more compact, high-power-density reactor that can utilize copper coils rather than the complex superconducting coils typically required for tokamaks.1
While the tokamak remains the most extensively investigated concept for achieving stable plasma equilibrium, the RFP is pursued as an alternative approach to address the engineering challenges associated with large-scale fusion reactors.12