Simulations of SIHI Spheromak Current Drive Experiments

The HIT-SI experiment has demonstrated stable sustainment of spheromaks. Determining how the underlying physics extrapolate to larger, higher-temperature regimes is of prime importance in determining the viability of the inductively-driven spheromak. It is thus prudent to develop and validate a computational model that can be used to study current results and study the effect of possible design choices on plasma behavior. An extended MHD model has been applied to simulate the HIT-SI and its successor HIT-SI3 across a range of injector frequencies (14, 36, 53, 68 kHz), and the results of those frequency scans will be shown, detailing general agreement with most experimental trends as well as where and what differences are observed. Behavior of a proposed future design with an alternate injector configuration will also be explored via extended MHD, and comparisons to earlier configurations made.