Technical Description
Toroidal plasmas are central to modern fusion energy experiments. Magnetic confinement in a toroidal geometry minimizes particle loss and allows for longer plasma sustainment. These systems generate and maintain extreme temperatures (millions of degrees Celsius), necessary for fusion reactions to occur.
Core Components
- Plasma: Ionized gas made of nuclei (like deuterium and tritium) and electrons.
- Vacuum Vessel: The toroidal chamber where plasma is formed and confined.
- Toroidal Magnetic Field Coils: Create magnetic fields wrapping around the torus to confine plasma particles.
- Poloidal Field Coils: Control plasma shape and stability within the torus.
- Heating Systems: Include ohmic heating, neutral beam injection, and radiofrequency heating.
- Diagnostics: Tools to monitor plasma temperature, density, and confinement performance.
Specifications
| Parameter |
Typical Value |
| Major Radius (R) | 1–6 m (tokamak devices) |
| Minor Radius (r) | 0.5–2 m |
| Plasma Temperature | ~150 million °C |
| Magnetic Field Strength | 2–5 Tesla |
| Plasma Current | 0.5–15 MA (Megaamperes) |
Fusion Devices Using Toroidal Plasma
- Tokamak: The most researched design; uses both toroidal and poloidal fields with a plasma current.
- Stellarator: Uses only external magnetic coils to achieve confinement, avoiding plasma current instabilities.
Challenges
- Plasma instabilities such as disruptions and edge localized modes (ELMs).
- Material endurance under high neutron flux and thermal stress.
- Achieving energy gain (Q > 1) in a sustainable manner.
Applications
- Nuclear fusion energy research
- Plasma physics studies
- Space propulsion (conceptual toroidal plasma engines)
