On the Influence of an Elevated Terrain on the Grounding Resistance of a Vertical Rod

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The lightning discharge current is characterized by a high-frequency spectrum extending from DC to about 10 MHz. The calculation of the grounding impedance is one of the most important aspects of designing lightning protection systems. The search for analy ...

In this thesis, we explored the effect of certain terrain-induced flow phenomena on the development of wind turbines sited in complex terrain. A combined experimental and analytical approach is used to study wind turbine wakes in different types of complex ...

Wind tunnel experiments are performed to investigate the effect of nacelle-to-rotor size on the wake of a wind turbine under different Reynolds numbers. Four different turbine configurations are tested, which vary in the rotor diameter and nacelle length a ...

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X-rays have been observed in natural downward cloud-to-ground lightning for over 20 years and in rocket-triggered lightning for slightly less. In both cases, this energetic radiation has been detected during the stepped and dart leader phases of downward n ...

Vertical-axis wind turbines are great candidates to enable wind power extraction in urban and off-shore applications. Currently, concerns around turbine efficiency and structural integrity limit their industrial deployment. Flow control can mitigate these ...

This article investigates the effects of voids, joint geometry, and test conditions on the quasi-static Mode I fracture performance of thick adhesive Double Cantilever Beam (DCB) joints such as those prevailing in wind industry and shipbuilding. The specim ...

In recent years, the electromagnetic time reversal (EMTR) theory has been successfully applied for locating various sources of disturbances, such as short-circuit faults, in power systems. In this paper, a theoretical analysis of the feasibility of applyin ...

This paper proposes a tower-foot grounding system model compatible with EMT programs which might be useful for the simulation of lightning transients in overhead lines. The proposed model is based on the solution of the telegrapher's equations and the appl ...

A floating platform for a wind turbine comprising a vertically arranged support; a toroidal body arranged horizontally and coaxially around said support; a plurality of connection elements which extends radially to connect the support to the toroidal body, ...

According to the International Energy Agency, the global net-zero emissions objective requires the installed wind power capacity to increase 11-fold between 2020 and 2050. The scientific community has recently voiced concerns about the logistic feasibility ...

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In this chapter, we present a review of recent progress in the modeling of lightning strikes to tall structures. Since some tall structures are struck by lightning several tens of times per year, they can be used as ground-truth to measure and calibrate th ...

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Vertical-axis wind turbines are excellent candidates to diversify wind energy technology, but their aerodynamic complexity limits industrial deployment. To improve the efficiency and lifespan of vertical-axis wind turbines, we desire data-driven models and ...

Controlling lightning is a long-time dream of mankind. Along with the rapid evolution of laser technologies, the idea to develop lightning protection based on filamentation of high-power ultrashort-pulse lasers emerged in the 1990s [1]. The goal of the Las ...

Lightning discharges, including cloud-to-ground (CG) and intracloud (IC) lightning, are known to emit electromagnetic pulses (EMPs) in a wide frequency band ranging from few Hz up to hundreds MHz [1]. During the breakdown and ionization processes (mostly f ...

In this thesis, we explore the best practice of simulating the wakes of the turbines under active yaw control (AYC) using large-eddy simulation (LES). In the first study, we validate the blade-element actuator disk model (ADM-BE) for a yawed wind turbine. ...

Fatigue life prediction of wind turbine rotor blades is a very challenging task, as their failure is led by different failure types that act synergistically. Inherent defects like wrinkles, fiber misalignments, and voids that can be introduced during fabri ...

An exact analytical expression for the electric field of the return stroke as excited by a propagating step current source is derived in this paper. This expression could be advantageously used to evaluate the disturbances caused by lightning on overhead l ...

On the Influence of an Elevated Terrain on the Grounding Resistance of a Vertical Rod

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High-frequency response of a hemispherical grounding electrode

Towards an improved understanding of wind turbine wakes in complex terrain

The effect of nacelle-to-rotor size on the wake of a miniature wind turbine

Non-contact sensing for anomaly detection in wind turbine blades: A focus-SVDD with complex-valued auto-encoder approach

Direct observations of X-rays produced by upward positive lightning

Optimal blade pitch control for enhanced vertical-axis wind turbine performance

Mode I fracture of thick adhesively bonded GFRP composite joints for wind turbine rotor blades

Assessment of the Feasibility of Applying the Electromagnetic Time Reversal Theory to Locate Defects in Grounding Electrodes

Tower-foot grounding model for EMT programs based on transmission line theory and Marti's model

Floating platform for a wind turbine

Dynamic stall characterisation and control for vertical-axis wind turbines

A wind tunnel study on cyclic yaw control: Power performance and wake characteristics

Modeling lightning strikes to tall towers

Characterization of wind turbine flow through nacelle-mounted lidars: a review

Time scales of dynamic stall development on a vertical-axis wind turbine blade

Laser-guided lightning using kHz filamentation at 1030 nm

Lightning interaction with the ionosphere

Wind Turbine Wakes in Active Yaw Control: Numerical and Theoretical Studies

Fatigue behavior and life prediction of wind turbine blade composite materials

Exact Expressions for Lightning Electromagnetic Fields: Application to the Rusck Field-To-Transmission Line Coupling Model