Theoretical Study On The Rule Of Plasma Temperature Decaying In The Process Of Lightning Dissipation

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 decaying with time at the given radii is quicker in the earlier and slower in the later; Furthermore, the higher original temperature is, the quicker decaying is; The temperature decays slower when the radii becomes larger. At the same time, the larger is the radii of lightning channel, the greater is the temperature grads; vice versa. According to the time and position of frozen temperature of NO, we can conclude primarily that NOx are produced in the channel of within 9mm radii and the time within 50 ms after lightning return strokes.According to the basic theory of lightning-generated NOx and using semi-empirical formulas, the rate of the principal chemical reactions involving NO during the dissipation process of lightning are calculated theoretically. The result shows that the compound plasmas produce NOx during the temperature decaying from 10000K to 2000K in lightning channel. With the temperature decreasing, the rates of creating N atom and O atom become slower;However, the rates of producing NO,O2 and N2 which are composed by NI and OI become quicker;The rates of the main reactions produced NO become the largest, when the temperature approaches 2000K or so. Therefore, it can be concluded primarily that the production of NO reaches maximum in the channel this moment for a given reactant concentration. As we know that lightning is a significant source of nitrogen oxide to the atmosphere, this work will give some reference data to the research of lightning producing nitrogen oxide and the effects on the local climate.