Wind energy conversion is contributing significantly to the new clean transition but, up now, such contribution mainly driven by large multi-MW windfarms. On other hand, recent needs in terms of distributed production are revealing a interest small-scale wind technologies for residential and urban applications. In this context, vertical axis turbines (VAWT) often most valid choice from point view building integrating possibilities, but it well known that they suffer considerable gap...

This study presents experimental and numerical investigation for the effect of number blade (solidity) on power thrust coefficients a small-scale horizontal-axis wind turbine HAWT. An set- up was installed rotors with different blades, i.e. three, five six, at tip speed ratios, in closed-circuit open-test section tunnel. The obtained results from CFD simulations were performed to compare data measurements. In addition, there is lack information presented rotor flow field HAWT like vertical...

Abstract In this work, the combination effects on wind turbine performances of wakes and terrain‐driven flow are investigated. The test case is a subcluster four turbines from farm sited in southern Italy very complex terrain. layout, inter‐turbine distance rose result challenging performance scenery. analyzed, when blows west, through computational fluid dynamics numerical simulations experimental supervisory control data acquisition mining. Two intensity regimes several simulation setups...

Abstract The power production of the Lillgrund wind farm has been investigated by means SCADA data covering almost 10 years operation, wake models and numerical simulation tools, such as WindSim, OpenFOAM ORFEUS. analysis provided quantification losses blockage effects, results that enable a benchmark to assess uncertainty other methods industrial use. have analysed in terms global array efficiency for different directions, velocity stratification conditions. A comparison present with Jensen...

Condition monitoring of gear-based mechanical systems in non-stationary operation conditions is general very challenging. This issue particularly important for wind energy technology because most the modern turbines are geared and gearbox damages account at least 20% their unavailability time. In this work, a new method diagnosis drive-train bearings proposed: idea that vibrations measured tower instead gearbox. implies measurements can be performed without impacting turbine operation. The...

Ageing of technical systems and machines is a matter fact. It therefore does not come as surprise that an energy conversion system such wind turbine, which in particular operates under non-stationary conditions, subjected to performance decline with age. The present study presents analysis the deterioration age Vestas V52 installed 2005 at Dundalk Institute Technology campus Ireland. turbine has operated from October 2018 its original gearbox, subsequently been replaced 2019. Therefore, key...

Timely damage diagnosis of wind turbine rolling elements is a keystone for improving availability and eventually diminishing the cost energy: from this point view, it priority to integrate high-level practices into real-world operation maintenance farms. On basis, present study devoted formulation reliable methodologies supervision bearings, which possibly can be integrated in industrial practice. For reason, collaboration between company (ENGIE Italia), University Perugia Politecnico di...

Researchers within the International Energy Agency (IEA) Task 31: Wakebench have created a framework for evaluation of wind farm flow models operating at microscale level.The consists model protocol integrated with web-based portal benchmarking (www.windbench.net).This paper provides an overview building-block validation approach applied to wake models, including best practices and data processing procedures datasets from SCADA meteorological databases.A hierarchy test cases has been...

This work deals with wind turbine wakes in complex terrain. The test case is a cluster of four 2.3 MW turbines, sited very Their performances are studied through supervisory control and data acquisition (SCADA) data, suggesting relevant role the terrain distorting wake upstream turbines. experimental evidences stimulate deeper comprehension numerical modeling: computational fluid dynamics (CFD) simulations run, using Reynolds-averaged Navier–Stokes (RANS) formulation. A novel way elaborating...

The electric generator is estimated to be among the top three contributors failure rates and downtime of wind turbines. For this reason, in general context increasing interest towards effective turbine condition monitoring techniques, fault diagnosis generators particularly important. objective study contributing techniques for through a supervisory control data acquisition (SCADA) analysis method. work organized as real-world test-case discussion, involving damage Vestas V52 sited southern...

Due to the stochastic nature of source, wind turbines operate under non-stationary conditions and extracted power depends non-trivially on ambient working parameters. It is therefore difficult establish a normal behavior model for monitoring performance turbine most employed approach be driven by data. The curve relation between intensity widely performance. On grounds above considerations, recent trend regarding analysis consists incorporation main parameters (as, example, rotor speed or...

The wakes induced by the wind turbines are modeled with finite-volume code WindSim, based on solving of Reynolds Averaged Navier-Stokes (RANS) equations an Atmospheric Boundary Layer. RANS uncompressible flow solved a multigrid coupled solver (MIGAL); turbulence is closed RNG k-ɛ model. rotor turbine actuator disc providing resistive force which calculated from thrust coefficient curve turbine. axial can be distributed over swept area in three different manners: uniform, parabolic or...

Failing in bacteria isolation a significant number of infections might be due to the involvement microorganisms nonrecoverable culture media. The presence cannot ruled out nondividing cells or even bacterial products still capable promoting host immunological response. Antibiotic therapy, for example, induce block division and impossibility recovering In these cases, molecular method targeting DNA should used. this study, 230 clinical samples with culture-negative report obtained from 182...

Full-scale wind turbine is a mature technology and therefore several retrofitting techniques have recently been spreading in the industry to further improve efficiency of kinetic energy conversion. This kind interventions costly and, furthermore, improvement commonly estimated under hypothesis ideal conditions, but real ones can be very different because wake interactions and/or shear induced by terrain. A precise quantification gained environment precious. Wind turbines are subjected...

In the recent years, distributed energy production has been one of main research topics about renewable energies. The decentralization electric from wind resources raises issues reducing size generators, MW scale industrial farm turbines to kW scale, and possibly employing them in urban areas, where flow is complex extremely turbulent because presence buildings obstacles. On these grounds, use small-scale vertical axis small (VASWT) a valid choice for on-site generation (OSG), considering...

The widespread availability of wind turbine operation data has considerably boosted the research and applications for monitoring. It is well established that a systematic misalignment nacelle with respect to direction remarkable impact in terms down-performance, because extracted power first approximation proportional cosine cube yaw angle. Nevertheless, due fact farm practice field facing rotor estimated through anemometers placed behind rotor, it challenging robustly detect errors without...

The formation and evolution of laminar separation bubbles on a horizontal axis wind turbine blade in the transitional flow regime are investigated using Large Eddy Simulations. Both rotating translating cases element, based small turbine, analyzed to distinguish specific aerodynamic effects introduced by rotation. results demonstrated that case, roll-up vortices developed through Kelvin–Helmholtz instability appear shorter, inclined at varying angles along span, break down various locations...

We describe three main developments of our previous study the nonlinear yaw dynamics tail fins for small wind turbines [Khedr et al., J. Renewable Sustainable Energy 16, 053305 (2024)]. First, model constants derived from archived computational and experimental studies are adjusted by employing system identification (SI) to maximize model's agreement with tunnel tests. This adjustment was done high speeds, where bearing friction can be ignored. When starting a turbine at low speed, however,...