China
Africa
Explore chapters and articles related to this topic
Lasers for Thermonuclear Fusion
Published in Hitendra K. Malik, Laser-Matter Interaction for Radiation and Energy, 2021
In another kind of process, a magnetic field helps to confine the plasma. When there is no field, the particles move randomly and interact with the reactor vessel's wall. This may lead to cooling down the plasma making it difficult for fusion reactions. When magnetic fields are applied, the particles move in the spiral trajectory around the fields' lines, avoiding the vessel walls. The plasma confinement by magnetic field is classified into two systems, namely closed and open. The magnetic fields' lines start from the plasma forming a loop in the open in the closed system. The open system may work on the principle of mirror reflection (which is an open tube system with a magnetic field), magnetic well, or theta pinch theory and it may leak plasma more than the closed system. The plasma is trapped in the centre due to the weaker magnetic field in the middle and is stronger at the ends in this type of mirror reflection device.
Engineering Paradigms for Sheared-Flow-Stabilized Z-Pinch Fusion Energy
Published in Fusion Science and Technology, 2023
M. C. Thompson, B. Levitt, B. A. Nelson, U. Shumlak
The SFS Z pinch requires neither externally driven compression from the liquid wall nor access to the plasma from the bottom of the system through the blanket. Therefore, a fusion power core based on this plasma confinement technology can implement a thick liquid wall and blanket using a simple tank with internal baffles forming a weir wall. Zap Energy’s current working point design uses the eutectic mixture of lithium and lead LiPb (17% lithium and 83% lead), which is pumped into a volume and allowed to cascade over the rim of the weir wall under gravity to from the first wall and a cavity for the SFS Z-pinch plasma.[14] The pinch current terminates in the LiPb liquid at the bottom of the cavity. The LiPb has approximately the same resistivity at 600 K as stainless steel does at 300 K.[28]
Energy Confinement Dynamics and Some Properties of Plasma Self-Organization in ECRH Regime in the L-2M Stellarator
Published in Fusion Science and Technology, 2023
Aleksei Meshcheryakov, Irina Grishina
We emphasize that in phase 3, the plasma cools down without being subject to external actions; i.e., its behavior is regulated by the self-organization processes. The plasma properties in phase 3 of plasma confinement, presented in Figs. 2 and 3, are in good agreement with the concept of plasma self-organization mentioned above. For example, a sharp drop in the power loss after switching off the ECRH pulse is associated with rapid relaxation of the profiles of plasma pressure, formed under the action of ECRH, to the canonical profile. In the opinion of the authors, during further time evolution of the plasma, the profiles of plasma parameters remain canonical. In Fig. 3, for any concrete plasma energy in phase 3, the canonical pressure profiles have time to establish. Therefore, in phase 3, the plasma power loss will be minimal at any chosen energy. Indeed, Fig. 3 shows that in phases 1 and 2, at any plasma energy, the energy loss from the plasma is higher than in phase 3. Figure 3 also shows the power-law approximation of the experimental data for phase 3, Ploss(W) = P0·(W/W0)3.1 (solid green line), which describes the dependence of the minimum possible total energy loss on the plasma energy. This dependence is fundamental for the L-2M stellarator since it characterizes the plasma confinement with the help of the magnetic system of this facility.
A Forward Analytic Model of Neutron Time-of-Flight Signals for Inferring Ion Temperatures from MagLIF Experiments
Published in Fusion Science and Technology, 2022
Colin Weaver, Gary Cooper, Christopher Perfetti, David Ampleford, Gordon Chandler, Patrick Knapp, Michael Mangan, Jedediah Styron
The neutron-burn time history is characterized by a burn width and bang-time , which correspond to the full-width-at-half-maximum of the neutron-burn time history and the stagnation point, respectively.28,29 Since the DD and DT fusion reactions are the source of neutrons in a MagLIF experiment, the time history of thermonuclear neutron production can be directly related to the confinement time of the plasma. A sufficiently long plasma confinement time is important for achieving energy break-even in inertial confinement fusion experiments. Hence, extracting the neutron burn width from an nToF measurement is relevant for characterizing a MagLIF experiment. A Gaussian distribution was assumed according to the equation