H-mode Confinement
High-confinement operating regime in tokamaks characterized by a steep edge pressure barrier (pedestal) and doubled energy confinement time.
Governing formula
Energy Confinement Time τ_E(H-mode) ≈ 2 × τ_E(L-mode)
SI unit
s (Energy Confinement Time τ_E)
In depth
Discovered at ASDEX in 1982. Exceeding a threshold heating power suppresses turbulent edge plasma transport through E × B sheared flow layer creation, forming an insulating edge 'pedestal'.
Examples in the real world
ITER tokamak baseline operating scenario relying on H-mode to reach fusion ignition.