Numerical optimization at General Atomics

Numerical optimization plays a very important role in nuclear fusion, in tokamak design, in the design of experiments, and in plasma control. Numerical optimization schemes were developed at General Atomics to determine configurations with maximal β
_T
. This optimization led to the design of DIII-D with low aspect ratio dee-shaped plasmas capable of β
_T
⩾ 10% and β
_T
> 10% has been achieved on DIII-D. Most recently, optimization schemes are being developed to determine the location of sensors for optimal control. This is done by optimizing sensor location to minimize the condition number of the coil-loop inductance matrix. There are many different forms of optimization, the form used may vary greatly depending upon the problem to be solved. The details of several optimizations performed, illustrating why the numerical techniques and the constraints were chosen, will be presented. Also, the speed and storage available may determine the form of the optimizer.