本文提出了流体一化学动理学二维正电晕放电混合模型，该模型包含12种粒子间的27种化学反应，并且考虑光电离的影响．此外，在实验室内对该模型开展试验验证，单次脉冲波形及伏安特性曲线符合较好．基于上述模型，本文研究了在外施电压3kV时棒一板电极正电晕放电过程中的电场分布、电子温度分布、空间电荷分布的发展规律，并对电晕放电过程中粒子的成分进行了详细分析，讨论了电子、正负离子、中性粒子在放电过程中的生成规律及对电晕放电的影响．结果表明：在整个电晕放电过程中，电子温度分布和电场强度分布曲线相似，电子密度维持在10^19m-3左右，只发现带正电的等离子体特征．O4＋密度是放电过程中数量最多的正离子，O2＋和N2＋在二次电子发射过程中具有重要作用，O2-离子和O分别是负离子和中性粒子中数量最多的粒子，由于负离子和中性粒子在电晕放电过程中数量较小，因而起的作用相对较小．%Corona discharges are usually generated at sharp points, edges or on thin wires where the electric field is strongly concentrated. With the rapid development of extra and ultra high-voltage transmission lines, the air corona discharge becomes one of the critical problems associated with high-voltage lines, which can lead to the deterioration of insulation systems, power loss, radio noise. Corona discharge studies have been undertaken for many years, not only because of the scientific interest in the corona mechanism but also because of its practical engineering importance. Transient space charge distribution effect that is one of the important canses in the process of corona discharge, is closely related to the corona discharge mechanism and onset, self-sustaining. In this paper, we present an improved self-consistent, multi-component and two-dimensional plasma hybrid model for simulating the DC positive corona discharge under atmospheric environment. The model is based on the plasma hydrodynamics and the chemical dynamics, and it includes 12 species and 27 reactions. Besides, the photoionization effect is also considered in the proposed model. The simulation and the experiment on bar-plate electrode configuration with an inter-electrode gap of 5.0 mm at 2-5.5 kV are carried out. The discharge voltage-current characteristics and single pulse waveform are in good agreement with the experimental measurements. Based on this model, the electric field distribution, the electron temperature distribution, and the evolution of charged species distribution are investigated in detail. The results show that distributions of electron temperature and electric field have the same patterns, In the process of discharge, electron density is kept at 10^19 m-3 or so. O4+ is dominant compared with the other charged heavy species, and O+ and N+ play the key role in secondary electron emission: the unmbers of O~ and O are the largest in negative ions and neutral particle respectively, they play a negligible role in discharge process.
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