To ensure sufficient divertor target lifetime, the loss in plasma stored energy due to ELMs in ITER should be restricted to △W_(ELM) ≤ 1 MJ. Only in JET, by virtue of its size, can such energies be approached. This contribution examines the impact of large, Type I ELMs in high current H-mode JET discharges with ITER-relevant pedestal characteristics. The ELMs provoke strong radiation losses, mostly confined to the inner divertor volume. Although the data are scattered, the average magnitude of this loss is △E_(RAD)～ 0.5△W_(ELM). for △W_(ELM) < 0.55 MJ. For higher △W_(ELM), greater fractional radiation losses occur, reaching ～0.7,△W_(ELM) at △W_(ELM)～0.9 MJ, indicating enhanced impurity release. Even at the highest ELM energies, peak divertor target surface temperatures are too low for carbon sublimation, suggesting that thermal decomposition and/or ablation of thick co-deposited layers on the inner target may be occurring. On average, across the range of energies studied, ELMs are found to deposit between 3-4.5% of △W_(ELM) on main wall limiters. When applied to the data for a specific discharge in the series, the model of ELM filament parallel energy losses developed at JET requires radial ELM velocities in the interval 0.1_0.65 km s~(-1) to explain these deposited energy fractions.
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机译：为了确保有足够的滤光片目标寿命，应将ITER中ELM引起的等离子存储能量损失限制在△W_（ELM）≤1 MJ。只有在JET中，凭借其大小才能获得这种能量。此文稿检查了具有ITER相关基座特性的大电流I型ELM在高电流H模式JET放电中的影响。 ELM引起很大的辐射损失，主要限于内部分流器的体积。尽管数据分散，但这种损失的平均幅度为△E_（RAD）〜0.5△W_（ELM）。对于△W_（ELM）<0.55 MJ。对于更高的△W_（ELM），更大的分数辐射损失发生，达到约0.7，在△W_（ELM）〜0.9 MJ时达到△W_（ELM），表明杂质释放增强。即使在最高ELM能量下，偏滤器的峰值目标表面温度对于碳的升华而言仍然太低，这表明内部目标上的厚共沉积层可能发生热分解和/或烧蚀。平均而言，在所研究的整个能量范围内，ELM被发现在主壁限制器上沉积3-4.5％的△W_（ELM）。当应用于系列中特定放电的数据时，JET开发的ELM灯丝平行能量损失模型需要在0.1_0.65 km s〜（-1）范围内的径向ELM速度来解释这些沉积的能量分数。
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