中文摘要：

利用流体运动方程、连续性方程和能量守恒方程,对自然闪电回击后的消散过程建立数学模型,计算了等离子体温度随时间和空间的变化规律.结果分析表明：在相同的通道半径处,前期温度随时间衰减较快,后期较慢,并且,初始温度越高,衰减越快;随着半径的增大,温度的衰减幅度逐渐减小.同一时刻,半径小的位置温度梯度较小,半径大的位置温度梯度较大.由衰减到NO冻结温度的时间和位置,初步推断氮氧化物（NOx）生成主要在闪电冲击波之后50ms内、半径R=9mm的等离子体通道内.

英文摘要：

The temporal and spatial distributions of the plasma temperature during the dissipation process of lightning are calculated theoretically by applying the equation of motion, the equation of continuity and the equation of energy conservation of hydrostatics. The result shows that the temperature decay at a given radius is quicker in the earlier stage and slower in the later stage; Furthermore, the higher the original temperature, the quicker the decay. The temperature decays slower when the radius becomes larger. At the same time, the larger the radius of lightning channel, the greater the temperature gradient, and vice versa. According to the time and position of freezing temperature of NO,we can conclude primarily that NOx are produced in the channel of less than 9 mm radius in the time within 50 ms after the lightning return stroke.