This work is the result of a student project in which a Java program (Applet) was developed. With this applet, you can compute electric and magnetic fields produced by a lightning return stroke to an elevated structure
The work is carried within an international research project involving the Swiss Federal Institute of Technology (J.L. Bermudez, D. Pavanello, F. Rachidi), University of Bologna (A. Borghetti, C.A. Nucci, M. Paolone), Western University of Applied Sciences (M. Rubinstein), University of Florida (V.A. Rakov) and University of Toronto (W. Janischewskyj)
The applet includes the effect of a strike object (tower) which was represented by a lossless transmission line with constant and frequency-independent reflection coefficients at the top and at the bottom of the tower [F. Rachidi, V. Rakov, C.A. Nucci, J.L. Bermudez, “The Effect of Vertically-Extended Strike Object on the Distribution of Current Along the Lightning Channel,” Journal of Geophysical Research, vol. 107, pp. 4699, 2002], [D. Pavanello, F. Rachidi, M. Rubinstein, J.L. Bermudez, C.A. Nucci, “Electromagnetic Field Radiated by Lightning to Tall Towers: Treatment of the Discontinuity at the Return Stroke Wavefront,” Journal of Geophysical Research, vol. 109, pp. D06114 – 7 pages, 2004.].
To compute the electromagnetic fields, you must proceed as follows:
- Define the geometrical/electrical parameters of the problem (Lightning channel height, distance and height of the observation point, strike object’s height and reflection coefficients at its extremities).
- Define the values for the parameters of the channel-base current (double exponential and/or double Heidler’s functions) and the return-stroke speed.
- Select (one or more) of the engineering return stroke models.
- Select the field components to be computed.
- Select time window and time step and run the program.
After the time required to perform the simulation, you will be invited to observe the calculated field waveforms. In the figure, you have a zoom tool to observe more details in the waveforms and you can also produce text files in the figure menu to export the data for a further treatment.
Enjoy your time and do not hesitate to contact us for details.
Regards, EMC Group Contact: Farhad.Rachidi@epfl.ch