The properties of a non-stationary corona discharge were numerically calculated for a grounded rod as a function of wind velocity. The model took into account light ions and aerosol ions. The calculations were carried out for a slowly varying thundercloud electric field and when this field was enhanced by the charge of an approaching downward leader. It was shown that, in a slowly varying thundercloud electric field, the peak corona current varies noticeably with wind velocity. The space distribution of ions is affected by wind only at sufficiently large distances from the rod tip. The effect of wind on this distribution is small at distances of 1-2 m at which an upward connecting leader is initiated and a question is solved whether or not it will survive. This result could be predicted based on the properties of a corona. In the immediate vicinity of the rod tip, the local electric field is high and the ion drift velocity is much larger than the wind velocity; therefore, the effect of wind on the ion movement is not important in this region. The effect of wind on the properties of a corona discharge was also studied when the thundercloud electric field was enhanced by the charge of an approaching downward leader. It was shown that wind does not affect noticeably initiation and viability of an upward connecting leader. Here, wind has no time to affect the discharge processes near a grounded object for a short period of time for which a downward leader approaches to it. As a result, the attractive radius for a corona-producing lightning rod and other grounded objects and their ability to attach lightning are almost independent of wind. The effect of wind could be important only for upward lightning discharges initiated and developed from very high (> 200 m) objects in a slowly varying thundercloud electric field.
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