Due to the greenhouse effect of SF ₆ , the search for new environmentally friendly substitute gases has become an urgent task for the electrical industry. In this article, we have employed a 2-D fluid model to study the characteristic of streamer discharges in the C ₄ F ₇ N-N ₂ mixture. The discharge process and insulation performance of the C ₄ F ₇ N-N ₂ mixture with different C ₄ F ₇ N content are compared under the same conditions. In a5.07% C ₄ F ₇ N-N ₂ mixture, the streamer expands continuously and reaches the top boundary quickly. In 7% and 13.1% C ₄ F ₇ N-N ₂ mixture, the streamer is gradually stagnated in the simulation domain. The streamer radius shows a decreasing trend, and a low electron density area appears behind the streamer head as the streamer moves forward. The streamer discharge simulation in 50% SF ₆ –50% N ₂ is also performed to compare its insulation performance to the C ₄ F ₇ N-N ₂ mixture. The results show that the discharge is suppressed more heavily in 13.1% C ₄ F ₇ N-N ₂ than in 50% SF ₆ –50% N ₂ . The influence of buffer gas is studied by comparing the discharge process in C ₄ F ₇ N-N ₂ and C ₄ F ₇ N-CO ₂ with 13.1% C ₄ F ₇ N content. It is found that the discharge is more easily to a breakdown in C ₄ F ₇ N-CO ₂ than that in C ₄ F ₇ N-N ₂ in our simulation configuration. The simulation provides a way to optimizing the buffer gas ratio of new environmentally friendly gases from a microscopic perspective.

中文翻译：

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C₄F₇N-N2放电动力学及缓冲气体影响的数值模拟

由于SF ₆的温室效应 ，寻找新的环保替代气体成为电气行业的当务之急。在本文中，我们采用二维流体模型来研究 C ₄ F ₇ NN ₂混合物中流注放电的特性 。比较了不同C ₄ F ₇ N含量的C ₄ F ₇ NN ₂混合物 在相同条件下的放电过程和绝缘性能 。在 a5.07% C ₄ F ₇ NN ₂混合后，流光不断膨胀并迅速到达顶部边界。在7%和13.1%的C ₄ F ₇ NN ₂混合物中，流注在模拟域中逐渐停滞。流注半径呈减小趋势，随着流注向前移动，流注头部后方出现低电子密度区域。还进行了 50% SF ₆ –50% N _{2 中}的流注放电模拟， 以将其绝缘性能与 C ₄ F ₇ NN ₂混合物进行比较。结果表明，在 13.1% C ₄ F ₇ NN _{2 中}放电受到更严重的抑制 比在 50% SF ₆ –50% N _{2 中} 。通过比较C ₄ F ₇ NN ₂和C ₄ F ₇ N-CO _{2 中}C ₄ F ₇ N含量为13.1% 的放电过程，研究了缓冲气体的影响 。发现在C ₄ F ₇ N-CO _{2 中}放电比在C ₄ F ₇ NN _{2 中}放电更容易击穿 在我们的模拟配置中。该模拟提供了一种从微观角度优化新型环保气体的缓冲气体比例的方法。