Magnetic Reconnections Stochastic-Adaptive Control for Plasma Fusion

In the paper presented a comprehensive investigation into a novel heating mechanism for pulsed fusion devices, specifically the Pulsed Reconnection Engine (PRE) applied to a Spheromak configuration. Conventional Ohmic heating becomes inefficient at reactor temperatures because classical plasma parallel resistivity drops according to the Spitzer relationship ( η _S ∝ T _e ^−3/2 ). Consequently, Compact Toroids often stall before reaching ignition temperatures, as they cannot overcome the radiation barrier, where impurity losses exceed heating power. To overcome this fundamental limit without resorting to expensive and bulky auxiliary heating methods like Neutral Beam Injection (NBI), we propose an Adaptive Stochastic Resonance (SR) control strategy. This system actively modulates an effective anomalous resistivity – physically realizable via Radio Frequency (RF) wave injection or Lower Hybrid Current Drive (LHCD) – to trigger magnetic reconnection events synchronized with the plasma’s natural magnetohydrodynamic modes. Using a rigorous 0D/2D two-fluid energy-balance model with realistic confinement assumptions ( τ _E = 0.1 s ), we demonstrate four key results: (1) The validity of a resistive diffusion model for tracking thermal evolution in force-free magnetic configurations; (2) The thermodynamic necessity of a two-fluid approach to capture Ion-Electron Decoupling; (3) The capability of SR control to trigger simultaneous multi-site reconnections, enabling Ohmic-like ignition in regimes where classical Ohmic heating fails; and (4) The detailed physical mechanism by which external actuation controls local resistivity. Simulation results show that the SR drive successfully heats Deuterium-Tritium ions from 0.1 keV to ≈ 30 keV, achieving a “Hot Ion Mode” ( T _i >> T _e ) that minimizes radiative losses. Furthermore, we demonstrate a Triple-Loop Control Architecture (Heating, Fueling, Safety) that stabilizes the burn, allowing the reactor to meet the Lawson Criterion and achieve self-sustaining ignition ( Q _fus → ∞ ) in a stable “Flat-Top” operational mode.