Prediction of high-k electron temperature fluctuation in an NSTX H-mode plasma
POSTER
Abstract
High-k temperature fluctuations $\tilde{T}_e$ in fusion plasmas are associated with electron-scale electromagnetic drift-wave type turbulence. High-k $\tilde{T}_e$ might contribute significantly to heat loss in a fusion reactor. However, no direct measurements of high-k $\tilde{T}_e$ have ever been made in any experiments and thus no validation work involves the quantity $\tilde{T}_e$. In this work, we run electron temperature gradient(ETG)-scale nonlinear gyrokinetic simulations of an NSTX H-mode with CGYRO. We will do a synthetic projection of high-k $\tilde{T}_e$ from simulation in NSTX which has never been done before. Comparison with high-k electron density fluctuation $\tilde{n}_e$ are made to demonstrate the advantages of predicted $\tilde{T}_e$ diagnostics and how critical it is for validation of transport models. The impact of $\tilde{T}_e$ on electron thermal transport are studied to answer the question whether ETG is the dominant turbulence mechanism or not.
*This work has been supported by US. D.O.E. contract DE-SC0019089. Computer sim- ulations were carried out at the National Energy Research Scientific Computing Center, supported by the Office of Science of the U.S. Department of Energy under Contract No. DE- AC02- 05CH11231 and at the MIT-PSFC partition of the Engaging cluster at the MGHPCC facility (www.mghpcc.org) which was funded by DoE grant number DE-FG02-91-ER54109.