Performance and Transport in ITER: Multi-Channel Validation in DIII-D ITER-like Conditions and Predictions of ITER Burning Plasmas via Nonlinear Gyrokinetic Profile Prediction

Performance and transport in ITER conditions has been studied extensively through gyrokinetic model validation in DIII-D ITER similar shape (ISS) plasmas and through nonlinear gyrokinetic profile prediction of the ITER baseline scenario (IBS). Dedicated experiments were performed in ISS conditions to compare nonlinear gyrokinetic profile predictions with measured kinetic profiles (ne, Te, Ti), heat and particle fluxes (Qe, Qi, Γe), turbulent fluctuations, and impurity transport across a large portion of the plasma minor radius (ρ = 0.3−0.8). Generally good agreement was found between simulation and experiment in the wide range of channels compared, providing confidence in applying gyrokinetic profile prediction to ITER conditions. Simulations of the ITER baseline scenario (IBS) suggest that ITER should obtain approximately its 500MW, Q = 10 goal. Levering new modeling techniques, simulations indicate that ITER may be able to be optimized to obtain significantly higher Q when operating near its baseline scenario and should still be capable of obtaining burning plasma conditions, despite RMPs degradation of the anticipated density pedestal. Simulations of IBS conditions with varying fuel ion (H, D, and D-T) were performed that suggest that stiff ITG turbulence present in the plasma core is unlikely to exhibit any significant isotope effect of energy confinement. This result is largely in disagreement with the τITER98−y2 scaling, but is consistent with recent updates to the energy confinement scalings such as τH20. The work reported here provides a comprehensive

针对国际热核聚变实验堆（ITER）工况下的等离子体性能与输运问题，已有大量研究通过DIII-D装置类ITER形状（ITER Similar Shape, ISS）等离子体中的回旋动理学（gyrokinetic）模型验证，以及ITER基准运行模式（ITER Baseline Scenario, IBS）的非线性回旋动理学剖面预测展开。研究团队在ISS工况下开展了专属实验，将非线性回旋动理学剖面预测结果与实测动理学剖面（电子密度nₑ、电子温度Tₑ、离子温度Tᵢ）、热流与粒子通量（电子热流Qₑ、离子热流Qᵢ、粒子通量Γₑ）、湍流涨落以及跨越等离子体大部分小半径（归一化小半径ρ=0.3−0.8）的杂质输运数据进行对比。在所对比的多类物理通道中，模拟结果与实验数据整体吻合良好，这为将回旋动理学剖面预测方法应用于ITER工况提供了可靠支撑。针对ITER基准运行模式（IBS）的模拟结果显示，ITER有望实现约500兆瓦、增益因子Q=10的既定目标。借助新型建模技术，模拟结果表明，在基准运行模式附近运行时，ITER可通过优化获得显著更高的Q增益因子；即便共振磁扰动（Resonant Magnetic Perturbations, RMPs）会导致预期的密度台基性能退化，ITER仍具备实现燃烧等离子体工况的能力。研究团队还开展了不同燃料离子（氢H、氘D、氘氚D-T）工况下的IBS模拟，结果显示等离子体芯区存在的刚性离子温度梯度模（Ion Temperature Gradient, ITG）湍流几乎不会表现出显著的能量约束同位素效应。该结果与τ_ITER98−y2能量约束定标律存在较大分歧，但与近期更新的能量约束定标律（如τ_H20）相一致。本文报道的研究工作提供了一套完整的