We report on simulation results of a 3+1 gyro-Landau-fluid (GLF) model in BOUT++ framework, which contributes to increasing the physics understanding of the edge turbulence. We find that there is no second stability region of kinetic ballooning modes (KBM) in the concentric circular geometry. The first unstable β of KBM decreases below the ideal ballooning mode threshold with increasing . In order to study the KBM in the real tokamak equilibrium, we find that the approximation of shifted circular geometry () is not valid for a high β global equilibrium near the second stability region of KBM. Thus we generate a series of real equilibria from a global equilibrium solver CORSICA, including both Shafranov shift and elongation effects, but not including bootstrap current. In these real equilibria, the second stability region of KBM are observed in our global linear simulations. The most unstable mode for different β are the same while the mode number spectrum near the second stability region is wider than the case near the first stability region. The nonlinear simulations show that the energy loss of an ELM keeps increasing with β, because the linear drive of the turbulence remains strong for the case near the second stability region during profile evolution.
我報告了在BOUT++框架下進行的3+1維迴旋-流體（GLF）模型模擬結果，這有助於增進對邊緣物理的理解。我們發現，在同心圓形幾何中，不存在動力學氣球模（KBM）的第二穩定區。隨著β的增加，KBM的第一不穩定邊界會低於理想氣球模的閾值。為了研究真實托卡馬克平衡中的KBM，我們發現移位圓形幾何的近似在高β、接近第二穩定區的全局平衡中不再有效。因此，我們利用全局平衡求解器CORSICA生成了一系列真實平衡，這些平衡包含了Shafranov移位和拉長效應，但未包含自舉電流。在這些真實平衡中，我們在全局模擬中觀察到了KBM的第二穩定區。對於不同的β值，最不穩定模態相同，而在第二穩定區附近的模態數譜比第一穩定區附近的更寬。非線性模擬表明，在剖面演化過程中，由於第二穩定區附近湍流的線性驅動仍然很強，ELM的能量損失隨著β的增加而持續增加。