Engineering topics
Publications and source records attributed to Bondiou, A..
An experiment was carried out in which 3-D mapping of VHF sources was compared to a 3-D description of the reflectivity and dynamics of associated cloud cells observed by a radar network. Data from 61 microbursts were analyzed and it was found that, in 93 pct. of the cases, electrical activity precedes outflow development. The results confirm that the peak in intracloud activity precedes the maximum value of the outflow.
Electrical measurements were conducted in 1987 and 1988 on streamer and leader discharges occurring during the first stages of a triggered flash. This paper describes the pulsing phenomenon observed at positive leader onset (typical pulsing rate 25 microns), and it is shown that the same process happened in the case of the ignition of a flash triggered in altitude; with a wire several hundred meters long, positive leader propagates alone for several ms before the ignition of the downward negative stepped leader.