Author: Jeffrey P. Freidberg
Requested Type: Poster
Submitted: 2018-02-28 13:47:45
Co-authors: A.J. Cerfon
MIT Plasma Science and Fusion Center
167 Albany St
Cambridge, MA 02139
We present a simple methodology for computing the design parameters of tokamaks for any value of the toroidal magnetic field. Our method is based on a sharply defined hierarchical application of established algebraic formulae and scaling laws, eventually leading to two coupled algebraic equations for the plasma temperature, major radius, and toroidal magnetic field. These equations are easy to solve numerically, and the design values that are obtained can be back-substituted to compute all relevant quantities, such as the plasma density, bootstrap current fraction, divertor heat load, neutron flux, etc.
We demonstrate that our simple approach leads to tokamak designs which are in agreement with more detailed design studies, such as the ARIES ACT I, ARIES ACT II, and MIT ARC tokamak designs. We also show that the standard tokamak fails: without at least one optimistic assumptions on the confinement time, MHD stability, or current drive efficiency, efficient steady-state operation leads to unrealistically large devices. Finally, we conduct parametric studies indicating the areas in which progress in plasma physics would lead to the most significant gains in terms of the size and desirability of a tokamak design.