高性能自持燃烧的氘氚等离子体

D-T plasma of self-sustained burning under high performance

在等离子体密度分布一定的情况下 ,从电子、离子的能量输运方程出发 ,对常规剪切和中心负剪切位形下高性能自持燃烧的氘氚等离子体进行了研究 .常规剪切下采用与能量约束改善因子H有关的Bohm热传导系数 ,中心负剪切下采用一个与磁剪切有关的Bohm gyro Bohm混合型的热传导系数 ,并考虑了α粒子反常扩散和动态反馈加热对氘氚自持燃烧的影响 .研究结果表明 ,常规剪切下当H≥ 3时 ,才有较大的能量输出 ,当H接近 4时无须动态反馈加热氘氚就能获得自持燃烧 ;在中心负剪切位形下 ,等离子体的运行性能更高 ,有更高的能量输出 ,一旦氘氚达到燃烧条件 ,无须动态反馈加热就能获得自持燃烧 ;α粒子的反常扩散对氘氚燃烧有较大影响 ,在常规剪切下 ,适当的反常扩散有利于燃烧 ,在中心负剪切情况下 ,反常扩散过大 ,氘氚将变得不能自持燃烧 ;

By adopting a Bohm-type thermal diffusion coefficient related to the energy confinement enhancement factor H within the conventional magnetic shear regime, and a mixed Bohm-gyro-Bohm thermal diffusion coefficient related to the shear within the negative central magnetic shear regime, considering the effect of the alpha particle anomalous diffusion and the dynamic feedback heating, and starting from energy transport of electrons and ions, we have studied the high performance self-sustaining burning deuterium-tritium plasma under a given plasma density profile for the two different kinds of magnetic shear regimes. Some conclusions are obtained: under the conventional shear, only when H greater than or equal to 3, the D-T burning can produce a large power output, and when H is larger than a certain value (H approximate to 4), D-T plasma self-sustained burning can be maintained without the dynamic feedback heating; under the negative central shear, the plasmas have a higher plasma performance and a larger power output than that under conventional shear, and D-T plasma self-sustained burning can be maintained without the dynamic feedback heating power, the suitable alpha particle diffusion is advantageous to D-T plasma burning under the conventional shear, and D-T self-sustained burning cannot be maintained under a large alpha particle anomalous diffusion for the negative central shear. The dynamic feedback heating power is important for sustaining D-T plasma burning under the conventional shear.