The Dynomak reactor system is the possible realization of economical fusion enabled by Imposed-Dynamo Current Drive (IDCD). IDCD could enable a spheromak commercial fusion development path.
• High CD (Current drive) efficiency improves over the tokamak.
• 30% CD efficiency enables the spheromak with high TBR and economically competitive with coal.
The HIT-SI, a cold (~10-20 eV) concept exploration experiment, has demonstrated such efficient sustainment with adequate confinement. (Reaches stability beta-limit with current drive power) IDCD.
The Steady Injective Helicity Injection method has achieved 90 kA toroidal current and current gains approaching 4.
NIMROD simulations of a bigger and hotter HIT show fluctuations may not break flux surfaces of stable equilibria
The Dynomak Reactor System Highlights
* Energy efficient IDCD for sustainment of a high beta spheromak configuration
* Immersive, molten-salt blanket system for first wall cooling, tritium breeding, and neutron moderation
* YBCO high-temperature superconductors for PF coil set
* SC-CO2 (supercritical carbon dioxide) secondary cycle (reviewed favorably by Westinghouse)
An economical fusion development path is proposed to reach Dynomak scale device
• Promising results from HIT-SI and NIMROD and an economical conceptual reactor design justifies Proof-of-Principle (PoP) experiment.
• PoP seeks to demonstrate adequate confinement at high temperature with IDCD on an inexpensive, pulsed machine.
• With successful PoP, the development path includes steady-state operation and nuclear engineering.
The Dynomak device is a spheromak with the aspect ratio of a spherical tokamak and shaped like a reversed field pinch. It is driven with only IDCD. The six inductive handle-shaped drivers use low-cost AC ( 40 kHz) power. Resistively heated to a few keV, the experiment has a 3.2 MA, 5 second pulse with a 2.5 s plasma current ramping duration. Its minor radius is 1.0 meter with aspect ratio 1.5. There is no toroidal field coil or anything linking the torus yet it has an engineering beta-limit as high as 16%. As a design-class project its reactor potential was assessed to be competitive with conventional power sources, undercutting coal and on par with natural gas with carbon capture. Costing using several ITER-developed components gave $1.2B.
• HIT-SI results indicate sustained spheromaks with pressure.
• Computer simulations indicate closed flux with large magnetic fluctuations.
• An IDCD driven spheromak enables economical fusion power [The Dynomak]
• Encouraging spheromak and RFP results and economical conceptual reactor justifies Proof-of-Principle experiment.
• IDCD driven spheromak development path may provide a cost effective approach to fusion energy.
$32 million Proof of Principle
The spheromak is a Magnetic Fusion Energy (MFE) configuration, which is a leading alternative to the tokamak. It has a simple geometry which offers an opportunity to achieve the promise of fusion energy if the physics of confinement, current drive, and pressure holding capability extrapolate favorably to a reactor