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Download or read book Status of Advanced Tokamak Scenario Modeling with Off-Axis Electron Cyclotron Current Drive in DIII-D. written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The status of modeling work focused on developing the advanced tokamak scenarios in DIII-D is discussed. The objectives of the work are two-fold: (1) to develop AT scenarios with ECCD using time-dependent transport simulations, coupled with heating and current drive models, consistent with MHD equilibrium and stability; and (2) to use time-dependent simulations to help plan experiments and to understand the key physics involved. Time-dependent simulations based on transport coefficients derived from experimentally achieved target discharges are used to perform AT scenario modeling. The modeling indicates off-axis ECCD with approximately 3 MW absorbed power can maintain high-performance discharges with q[sub min]> 1 for 5 to 10 s. The resultant equilibria are calculated to be stable to n= 1 pressure driven modes. The plasma is well into the second stability regime for high-n ballooning modes over a large part of the plasma volume. The role of continuous localized ECCD is studied for stabilizing m/n= 2/1 tearing modes. The progress towards validating current drive and transport models, consistent with experimental results, and developing self-consistent, integrated high performance AT scenarios is discussed.