Electromagnetic Fields Radiated by Lightning Return Stroke over Lossy Ground with Rock Formation
IEEE Transactions on Electromagnetic Compatibility, cilt.63, sa.5, ss.1444-1451, 2021 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 63 Sayı: 5
- Basım Tarihi: 2021
- Doi Numarası: 10.1109/temc.2020.3042667
- Dergi Adı: IEEE Transactions on Electromagnetic Compatibility
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Business Source Elite, Business Source Premier, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
- Sayfa Sayıları: ss.1444-1451
- Anahtar Kelimeler: Cylindrical coordinates, finite difference time domain (FDTD), lightning electromagnetic fields, lossy ground, rock formation
- Maltepe Üniversitesi Adresli: Hayır
Özet
Electromagnetic fields radiated by a lightning return stroke over lossy ground are calculated by finite difference time domain method in a two-dimensional cylindrical coordinate system. The considered ground model contains a rock formation for which four different geometries are defined: rectangle, triangle, circle, and random. Two electrical conductivities that are very low and very high compared to the conductivity of the ground are defined for the rock formation. Different scenarios are examined by computing horizontal electric field ${{\boldsymbol{E}}_{\boldsymbol{r}}}$, vertical electric field ${{\boldsymbol{E}}_{\boldsymbol{z}}}$, and azimuthal magnetic field ${{\boldsymbol{H}}_{\boldsymbol{\varphi }}}$ for both conductivities. In addition to the effect of different geometries, effects of spatial averaging, changing position of rock, different return stroke propagation speeds, observation points at different heights and different horizontal range distances are investigated adopting both first and subsequent return stroke currents as the source. The results show that ${{\boldsymbol{E}}_{\boldsymbol{z}}}$ and ${{\boldsymbol{H}}_{\boldsymbol{\varphi }}}$ fields are not much affected by geometry and conductivity change. However, for ${{\boldsymbol{E}}_{\boldsymbol{r}}}$ component, performances of rectangle and triangle geometries are close to each other and random one shows closest performance to that of the case when there is no rock inside the ground. On the other hand, the field values decrease as the rock conductivity increases for both stroke types.