Prediction of Alfvén eigenmode energetic particle transport in ITER scenarios with a critical gradient model
A reduced 1D, local, critical-gradient model of energetic particle (EP) transport by Alfvén eigenmodes (AEs)—the TGLF-EP+Alpha model—is applied to a much-studied ITER base case and variations with lower plasma current and lower current penetration. The TGLF-EP+Alpha model is a greatly reduced and computationally inexpensive model of EP transport. Such a reduced critical gradient model, while inapplicable to transport driven by strongly nonlinear or non-local abrupt events, is a valuable tool for scoping studies needed in scenario optimization for ITER and beyond. Furthermore, it relies on the assumption of critical-gradient AE transport with the critical EP density gradient determined by linear AE stability calculations in the TGLF gyro-Landau fluid code automated with the parallel-processed TGLF-EP wrapper. EP transport is treated with simultaneous drive of AEs by fusion-born alpha particles and fast ions born from a 1 MeV neutral beam injection (NBI) heating. The effect of simultaneous drive creates about 50% increased particle transport in both EP channels. High magnetic safety factor q and low shear $$\hat{s}$$ are generally destabilizing to AEs, but low shear tends to be more important. A tailored q-profile, steady-staterelevant scenario can reduce AE-induced EP redistribution by better than 25% over the ITER base case despite having half the total current.
- Research Organization:
- General Atomics, San Diego, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
- Grant/Contract Number:
- SC0018108; FG02-95ER54309
- OSTI ID:
- 1597824
- Journal Information:
- Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 1 Vol. 60; ISSN 0029-5515
- Publisher:
- IOP ScienceCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Analysis of Alfven eigenmode destabilization in ITER using a Landau closure model
Gyrokinetic simulation of global and local Alfvén eigenmodes driven by energetic particles in a DIII-D discharge