Direct comparison of energy confinement times for the NSTX discharges

The predictive simulations with the MMM8.1 model show the same trend as observed in experiments. The confinement times for the low plasma collisionality discharge are larger. However, the values of confinement time are systematically higher comparing to the confinement times derived from the experimental data. Most likely reason is missing transport from instabilities that are not part of MMM8.1 (such as microtearing modes).

Experimental energy confinement times

Experimental energy confinement times

Predicted energy confinement times

Predicted energy confinement times