Publications by Mohammad Azadifar

Related publications (80)

Electromagnetic Fields Associated With the M‐Component Mode of Charge Transfer

Marcos Rubinstein, Mohammad Azadifar, Davide Pavanello, Lixia He

In upward flashes, charge transfer to ground largely takes place during the initial continuous current (ICC) and its superimposed pulses (ICC pulses). ICC pulses can be associated with either M-component or leader/return-stroke like modes of charge transfe ...

2019

Evaluation of the performance characteristics of the European Lightning Detection Network EUCLID in the Alps region for upward negative flashes using direct measurements at the instrumented Säntis Tower

Farhad Rachidi-Haeri, Marcos Rubinstein, Mario Paolone, Davide Pavanello, Mohammad Azadifar, Carlos Alberto Romero Romero

In this paper, we present a performance analysis of the European Cooperation for Lightning Detection (EUCLID) lightning detection network using data obtained on lightning currents measured at the Santis Tower (located in northeastern of Switzerland) from J ...

Amer Geophysical Union2016

Characteristics of Upward Lightning Flashes

Mohammad Azadifar

In addition to the general aims of lightning research such as lightning physics and meteorology, the study of upward lightning is of particular importance in protection of tall objects such as wind turbines and telecommunication towers. It also helps us in ...

EPFL2018

Analysis of lightning electromagnetic field propagation in mountainous terrain and its effects on ToA-based lightning location systems

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Zhaoyang Wang, Keyhan Sheshyekani

In this paper, we analyze the propagation effects on lightning-radiated electromagnetic fields over mountainous terrain by using a three-dimensional (3-D) finite difference time domain (FDTD) method. We also discuss the time delay error in the time-of-arri ...

Amer Geophysical Union2016

Partial discharge localization in power transformers using acoustic time reversal

Florent Quentin Aviolat, Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami

The localization of partial discharges (PD) is important to monitor the conditioning of high voltage insulator materials. One of the key components in power grids is the high power transformer. Localization of PDs in these pieces of equipment can increase ...

Elsevier2022

An Extension of the Guided Wave M‐Component Model Taking Into Account the Presence of a Tall Strike Object

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Quanxin Li

We present in this paper an extension of the guided-wave M-component model of Rakov et al. considering the presence of a vertically elevated strike object. The tall object is represented as a lossless, uniform transmission line. Expressions for the current ...

2021

Measurement and Modeling of Both Distant and Close Electric Fields of an M‐Component in Rocket‐Triggered Lightning

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi

Simultaneous measurements of current and multiple‐station electric fields associated with a 5.4‐kA‐peak M‐component in rocket‐triggered lightning are presented in this study. A close‐range electric field measurement site was located northeast of the trigge ...

2020

Partial Discharge Localization Using Time Reversal: Application to Power Transformers

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami

In this work, we present a novel technique to locate partial discharge (PD) sources based on the concept of time reversal. The localization of the PD sources is of interest for numerous applications, including the monitoring of power transformers, Gas Insu ...

2020

A New Engineering Model of Lightning M Component That Reproduces Its Electric Field Waveforms at Both Close and Far Distances

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Quanxin Li

We present a new engineering model for the M component mode of charge transfer to ground that can predict the observed electric field signatures associated with this process at various distances, including (a) the microsecond-scale pulse thought to be due ...

2019

A review of the modeling approaches of the lightning M-component with special attention to their current and electric field characteristics

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Carlo Alberto Nucci

In this paper, we present the characteristics of current, electric fields and modeling approaches of lightning M-component mode of charge transfer. We consider both the classical M-components (occurring after return strokes) and M-component-type ICC (Initi ...

Elsevier2023

An Analysis of Current and Electric Field Pulses Associated With Upward Negative Lightning Flashes Initiated from the Säntis Tower

Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Lixia He

We present a study on the characteristics of current and electric field pulses associated with upward lightning flashes initiated from the instrumented Säntis Tower in Switzerland. The electric field was measured 15 km from the tower. Upward flashes always ...

2018

The Polarity Reversal of Lightning‐Generated Sky Wave

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Wenhao Hou

The polarity reversal of the lightning‐generated first sky wave as a function of the observation distance is studied using a novel approach combining the finite‐difference time domain (FDTD) method and the superposition principle of electromagnetic waves. ...

2020

A Study of a Large Bipolar Lightning Event Observed at the Säntis Tower

Farhad Rachidi-Haeri, Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar

An unusual negative lightning flash was recorded at the Säntis Tower on June 15, 2012. The flash did not contain an initial continuous current typical of upward negative lightning, which is the most common type of event at the Säntis Tower. The flash conta ...

2019

Meteorological conditions during self-initiated upward lightning at the Säntis tower (Switzerland)

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Antonio Sunjerga, Amirhossein Mostajabi, Jacopo Grazioli, Nikola Besic

Meteorological conditions favoring the initiation of upward lightning from tall structures have been only poorly investigated so far. In addition to the scientific interest in this subject, it has practical applications to risk assessment for lightning occ ...

2019

Modeling of Different Charge Transfer Modes in Upward Flashes Constrained by Simultaneously Measured Currents and Fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Mario Paolone, Davide Pavanello, Mohammad Azadifar, Quanxin Li, Lixia He

The purpose of the paper is to investigate charge transfer modes in upward lightning flashes by means of numerical simulation constrained by concurrent observations of electromagnetic fields and currents. In particular, we focus on different types of pulse ...

2018

Localization of Electromagnetic Interference Sources Using a Time-Reversal Cavity

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami

In this article, we propose and implement a novel technique to locate electromagnetic interference (EMI) sources using the concept of time-reversal (TR) cavity. We show in an intuitive manner that reflections from the surfaces of a cavity can emulate an in ...

2021

LMA Observation of Upward Flashes at Santis Tower: Preliminary Results

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi

Lightning striking tall towers is mainly of the upward lightning type, which is characterized by the absence of a first return stroke and the presence of an initial continuous current (ICC) with or without superimposed pulses. The Santis Tower is 124 m tal ...

IEEE2018

Analysis of lightning-ionosphere interaction using simultaneous records of source current and 380 km distant electric field

Farhad Rachidi-Haeri, Marcos Rubinstein, Mario Paolone, Davide Pavanello, Mohammad Azadifar

We present simultaneous current and wideband electric field waveforms at 380 km associated with upward lightning flashes initiated from the Santis Tower, Switzerland. To the best of our knowledge, the dataset presented in this study includes the first simu ...

Elsevier2017

Assessing the Efficacy of a GPU-Based MW-FDTD Method for Calculating Lightning Electromagnetic Fields Over Large-Scale Terrains

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami

This article presents for the first time an OpenACC (Open accelerators)-aided Graphics Processing Unit (GPU)-based approach adopting a 3D moving window finite difference time domain (MW-FDTD) method for calculating lightning electromagnetic fields over lar ...

2020

Analysis of a bipolar upward lightning flash based on simultaneous records of currents and 380-km distant electric fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Amirhossein Mostajabi

In this paper, we present and discuss simultaneous records of current and wideband electric field waveforms at 380 km distance from the strike point associated with an upward bipolar flash initiated from the Säntis Tower. The flash contains 23 negative str ...

Elsevier2019