Electromagnetic fields of lightning return stroke in presence of a vertically stratified ground

摘要

Electrical parameter such as conductivity and permittivity of the ground are varies depends on terrain conditions. These parameters can affects lightning electromagnetic fields (LEMFs) observed at particular point from the striking location. In this study, the results of LEMFs in the presence of vertically stratified ground arereported. Lightning return stroke channel current is modeled using the modified transmission line with exponential current decay (MTLE)engineering model. LEMFs over vertically stratified ground is obtained by sort out the LEMFs in the perfect ground case; then proceed through generalized frequency domain formulas and using attenuation function. The effect of land and sea-water (mixed path) stratification on LEMFs is discussed for two layered(vertically)ground. The analysis is carried out for different distances (10km to 100km) and conductivities (0.1 to 0.001S/m). Result of LEMFs for vertically stratified conduction is compared with the prefect ground (characterized by their electric conductivity and permittivity)and reported.