Abstract. In this work, the vortex-induced vibration (VIV) phenomenon affecting a wind turbine airfoil section at 90° incidence is analysed with two numerical approaches, two-dimensional (2D) setup of airfoil, simulated using unsteady Reynolds-averaged Navier–Stokes equations, and three-dimensional (3D) span-to-chord aspect ratio 1, employing delayed detached-eddy simulation model. A constant inflow velocity considered for Reynolds number around 2×106. The only structural degree freedom...

The influence of anemometer rotor shape parameters, such as the cups' front area or their center rotation radius on anemometer's performance was analyzed. This analysis based calibrations performed two different anemometers (one magnet system output signal, and other one an opto-electronic signal), tested with 21 rotors. results were compared to ones resulting from classical analytical models. clearly showed a linear dependency both calibration constants, slope offset, radius, cups also...

Wind-flow pattern over embankments involves an overexposure of the rolling stock travelling on them to wind loads. Windbreaks are a common solution for changing flow characteristic in order decrease unwanted effects induced by presence cross-wind. The shelter effectiveness set windbreaks placed railway twin-track embankment is experimentally analysed. A two-dimensional tunnel tests undertaken and results corresponding pressure tap measurements section typical high-speed train herein...

Turbulent wind fields representing realistic atmospheric conditions are required for turbine load calculations. For a statistically stationary situation, the loads on depend, among other characteristics, spectra and spatial coherences of velocity field in rotor plane (i.e. cross-power spectral density matrix). In this study, novel approach is proposed to optimally calibrate parameters vector autoregressive model reproducing predefined target matrix be used synthetic generation turbulent...

Abstract Sequential methods for synthetic realisation of random processes have a number advantages compared with spectral methods. In this article, the determination optimal autoregressive (AR) models reproducing predefined target autocovariance function process is addressed. To end, novel formulation problem developed. This linear and generalises well-known Yule-Walker (Y-W) equations recent approach based on restricted AR (Krenk-Møller approach, K-M). Two main features characterise...

Abstract We have determined the normal Reynolds stresses and spectra of wind velocity over a 1:115 scale mock‐up Bolund hill. The experiment was run in neutral boundary layer tunnel using 3‐component hot‐wire velocimetry, 2‐component particle image high‐precision traversing system. Spectra been at different points along transects 2 5 m height above ground level. for 270° direction two numbers, , based on maximum hill free speed this height. Our results show how normalized power spectral...

Winds as an environmental factor can cause significant difficulties for the railway system operation. The overhead has been particularly vulnerable to cross-winds related problems, such development of undamped oscillations due galloping phenomenon. installation windbreaks decrease aerodynamic loads on train affect overheads triggering cable galloping. One essential parameter indicate influence parapet wake catenary contact wire is turbulence intensity. In this paper results experimental...

In a crosswind scenario, the risk of high-speed trains overturning increases when they run on viaducts since aerodynamic loads are higher than ground. order to increase safety, vehicles sheltered by fences that installed viaduct reduce experienced train. Windbreaks can be designed have different heights, and with or without eaves top. this paper, parametric study total 12 fence designs was carried out using two-dimensional model train standing viaduct. To asses relative effectiveness...

A measurement investigation, at ADIF's test site the O Eixo viaduct which is on Spanish Santiago-Ourense high speed railway line, has been carried out during last year. The main goal of investigation to study effect cross-wind overheads (catenaries) and influence presence windbreaks wind-induced motion overhead. description presented in this paper, including installed windbreaks, sensor power supply systems. Three catenary spans instrumented center point span contact wire with one ultrasonic...

An approach to obtain autoregressive models for generating synthetic time series in a single point with pre-defined von Kármán spectrum is presented. Statistical stationarity assumed. Under the premise of proposed theoretical expression power spectral density model used regression coefficients. This avoid aliasing effect which may appear when obtained reproduce given target autocovariance function. A genetic algorithm achieve an optimal model. compared by Gallego-Castillo et al. where...

A wide variety of models have been proposed to assess the effect vortex shedding loads on dynamics bluff bodies. To best authors' knowledge, a critical review such applied wind turbine towers has not carried out. comparison is made in present work three well-known models, ranging from simplest type or forced system model, through B fluidelastic C coupled model. Time-marching simulations are performed using classical modal analysis an isolated tapered tower subjected sheared and turbulent...

Abstract Large edgewise vibrations due to vortex shedding can be suffered by a wind turbine blade when the rotor is stopped or idling and there massively separated flow. High-fidelity simulations of these vortex-induced (VIV) with full-blade model are very computationally expensive, so currently reported results this type limited short time series reduced parameter spaces, far from being sufficient predict lock-in range other characteristics full-scale response VIV under real conditions....

Abstract. In this work, the Vortex-Induced Vibrations (VIV) phenomenon affecting a wind turbine airfoil section is analysed with two numerical approaches, two-dimensional (2D) setup of airfoil, simulated using Unsteady Reynolds-averaged Navier–Stokes equations, and three-dimensional (3D) span-to-chord aspect ratio 1, employing Delayed Detached Eddy Simulation model. A constant inflow velocity normal to chord considered, for Reynolds number around 2 × 106. The only structural degree freedom...

Rotational sampling is of paramount importance in the loading wind turbine blades due to turbulence We revisit classical model rotational longitudinal component a statistically stationary, homogeneous, isotropic turbulent velocity field experienced by point rotating plane perpendicular mean velocity. As well known, this simplest frame work, since it allows determine non-dimensional spectrum terms frequency and only two more non dimensional parameters, radial position speed. systematize...

Presentamos una experiencia piloto de aprendizaje sobre el uso Realidad Virtual Inmersiva (VR) y Aumentada (AR), con objetivo facilitar la comprensión dinámica compleja rotores, a estudiantes Grados en Ingeniería Aeroespacial. Las experiencias VR/AR permiten visualizar los movimientos las palas rotores (hélices, aerogeneradores helicópteros) así como campos vectoriales acciones externas (aerodinámicas, inerciales gravitatorias) que originan esos movimientos. Se consulta pros contras...

Sequential methods for synthetic realisation of random processes have a number advantages compared with spectral methods. In this article, the determination optimal autoregressive (AR) models reproducing predefined target autocovariance function process is addressed. To end, novel formulation problem developed. This linear and generalises well-known Yule-Walker (Y-W) equations recent approach based on restricted AR (Krenk-Moller approach, K-M). Two main features characterise introduced...