The early streamer emission principle does not work under natural lightning!
2007 (English)In: IX International Symposium on Lightning Protection, 2007Conference paper (Refereed)
An appropriate evaluation of the efficiency of airterminals is a key factor for the discussion of the claimedadvantages of the Early Streamer Emission devices ESEcompared to the conventional Franklin rods. In order todiscuss the physical basis and validity of the ESE claim, aself-consistent physical model is used to simulate theperformance of an air terminal under laboratory and undernatural lightning conditions. It is theoretically shown thatthe early initiation of streamers can indeed lead to the soonerinitiation of a self-propagating positive leader in a laboratorylong air gap under switching voltages. However, this is notthe case for positive leaders initiated from the same terminalunder the influence of the electric field produced by thedescent of a downward moving lightning leaders. The timeevolution of the leader development under natural conditionsis different to the case in laboratory, where the leaderinception condition is closely dependant upon the streamerinititation. This is mainly because of the differences in thetime variation of the electric field applied in laboratory andthat produced by the approach of the downward leader.Therefore, it is found that the claimed similarity between theswitching electric fields applied in laboratory and the electricfield produced by the descent of a negative downward leader,used in the literature to extrapolate the early streameremission principle to natural lightning, is not true.
Place, publisher, year, edition, pages
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-74192OAI: oai:DiVA.org:kth-74192DiVA: diva2:489285
IX International Symposium on Lightning Protection. Foz do Iguaçu, Brazil. 26th-30th November 2007
QC 201205232012-02-022012-02-022012-05-23Bibliographically approved