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电子输运系数是确保低温等离子体建模准确性的关键因素, 通过模拟电子的输运过程可对其数值求解. 在模拟电子输运时, 电子和中性粒子碰撞后的散射和能量分配方式有多种处理方法. 为了研究不同处理方法对电子输运系数的影响, 本文基于蒙特卡罗碰撞方法, 建立了电子输运系数的计算模型, 模拟约化电场10—1000 Td (1 Td = 10–21 V·m2)氢原子气中的电子输运过程. 计算结果表明, 各向同性假设对电子输运系数的影响随电场强度增加而增加, 但即使对于较低的约化电场(10 Td), 各向异性散射假设下电子的平均能量、通量迁移率和通量扩散系数也分别比各向同性假设下的值高38.34%, 17.38%和119.18%. 不同的能量分配方式对中高电场强度下(> 200 Td)的电子输运系数影响较为显著. 在高电场时, 均分法计算得出的电子平均能量、通量迁移率和通量扩散系数均小于零分法对应的值, 汤森电离系数则相反. Opal法得出的电子输运系数介于均分法和零分法之间. 此外, 考虑各向异性散射时, 不同能量分配方式对输运系数的影响高于各向同性. 本研究表明, 在计算电子输运系数时需要考虑各向异性的电子散射, 高电场条件下尤其要注意能量分配方式的选择.The veracity of a low temperature plasma model is limited by the accuracy of the electron transport coefficient, which can be solved by simulating the electron transport process. When simulating the transport properties of electrons, there are a variety of approaches to dealing with the scattering of electrons and energy partition between the primary-electrons and secondary-electrons after electron-neutral particles’ collision. In this paper used is a model based on the Monte Carlo collision method to investigate the influence of scattering method and energy partition method on the electron transport coefficient. The electron energy distribution function, electron mean energy, flux mobility and diffusion coefficients, as well as the Townsend ionization coefficients are calculated in the hydrogen atom gas under a reduced electric field from 10 to 1000 Td. The calculation results show that the influence of the isotropic scattering assumption on the electron transport coefficients increases with reduced electric field increasing. However, even under a relatively low reduced electric field (10 Td), the calculated mean energy, flux mobility, and flux diffusion coefficient of electrons under the assumption of anisotropic scattering are 39.68%, 17.38% and 119.18% higher than those under the assumption of the isotropic scattering. The different energy partition methods have a significant influence on the electron transport coefficient under a medium-to-high reduced electric field (> 200 Td). Under a high electric field, the mean energy, flux mobility and flux diffusion coefficient calculated by the equal-partition method (the primary and secondary electrons equally share the available energy) are all less than the values from the zero-partition method (the energy of secondary-electrons is assigned to zero). While the change of Townsend ionization coefficient with reduced electric fields shows a different trend. The electron transport coefficient obtained by the Opal method lies between the values from the equal-partition method and the zero-partition method. In addition, considering the anisotropic scattering, the influence of energy partition method on the transport coefficient is higher than that under the assumption of isotropic scattering. This study shows the necessity of considering the anisotropic electron scattering for calculating the electron transport coefficient, and special attention should be paid to the choice of energy partition method under a high reduced electric field.








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