The BOUT++ six-field turbulence code is used to simulate the ITER 11.5 MA hybrid scenario and a brief comparison is made among ITER baseline, hybrid and steady-state operation (SSO) scenarios. Peeling–ballooning instabilities with different toroidal mode numbers dominate in different scenarios and consequently yield different types of ELMs. The energy loss fractions (ΔWped/Wped) caused by unmitigated ELMs in the baseline and hybrid scenarios are large (∼2%) while the one in the SSO scenario is dramatically smaller (<1%), which are consistent with the features of type-I ELMs and grassy ELMs respectively. The intra ELM divertor heat flux width in the three scenarios given by the simulations is larger than the estimations for inter-ELM phase based on Goldston's heuristic drift model. The toroidal gap edge melting limit of tungsten monoblocks of divertor targets imposes constraints on ELM energy loss, giving that the ELM energy loss fraction should be smaller than 0.4%, 1.0%, and 1.2% for ITER baseline, hybrid and SSO scenarios, correspondingly. The simulation shows that only the SSO scenario with grassy ELMs may satisfy the constraint.
BOUT++六場湍流代碼被用於模擬ITER 11.5 MA混合運行方案，並對ITER基準方案、混合方案和穩態運行（SSO）方案進行了簡要比較。具有不同環向模數的剝離-氣球模不穩定性在不同方案中占主導地位，從而產生不同類型的邊界局域模（ELM）。在基準方案和混合方案中，未緩解的ELM導致的能量損失份額（ΔWped/Wped）較大（∼2%），而在SSO方案中則顯著較小（<1%），這分別與I型ELM和草型ELM的特徵相一致。三種方案中模擬給出的ELM期間偏濾器熱流寬度大於基於Goldston啟發式模型對ELM間期階段的估計值。鎢單塊偏濾器靶板的環向間隙邊緣熔化極限對ELM能量損失施加了約束，給出ELM能量損失份額在ITER基準方案、混合方案和SSO方案中應分別小於0.4%、1.0%和1.2%。模擬結果表明，只有具有草型ELM的SSO方案可能滿足該約束條件。