4,377
edits
Magnetic shear: Difference between revisions
no edit summary
No edit summary |
No edit summary |
||
| Line 5: | Line 5: | ||
Thus, in 3 dimensions, the shear is a 3 x 3 tensor. | Thus, in 3 dimensions, the shear is a 3 x 3 tensor. | ||
In the context of magnetic confinement, and assuming the existence of toroidally nested magnetic flux surfaces, the only relevant variation of the direction of the magnetic field is the radial gradient of the rotational transform (field line pitch). The latter is defined as | In the context of magnetic confinement, and assuming the existence of toroidally nested magnetic flux surfaces (cf. [[MHD equilibrium]]), the only relevant variation of the direction of the magnetic field is the radial gradient of the rotational transform (field line pitch). The latter is defined as | ||
:<math>\frac{\iota}{2 \pi} = \frac{d \psi}{d \phi}</math> | :<math>\frac{\iota}{2 \pi} = \frac{d \psi}{d \phi}</math> | ||