A5020566060- Wind Energy Research and Development
- Wind and Air Flow Studies
- Nuclear physics research studies
- Fluid Dynamics and Vibration Analysis
- Nuclear Physics and Applications
- Particle physics theoretical and experimental studies
- Energy Load and Power Forecasting
- Radiation Detection and Scintillator Technologies
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Aerodynamics and Fluid Dynamics Research
- X-ray Spectroscopy and Fluorescence Analysis
- Ocean Waves and Remote Sensing
- Wind Turbine Control Systems
- Atomic and Subatomic Physics Research
- Particle Detector Development and Performance
- Structural Health Monitoring Techniques
- High-Energy Particle Collisions Research
- Icing and De-icing Technologies
- Probabilistic and Robust Engineering Design
- Neutrino Physics Research
- Acoustic Wave Phenomena Research
- Geophysics and Gravity Measurements
- Fluid Dynamics and Turbulent Flows
- Meteorological Phenomena and Simulations
MAX IV Laboratory
2008-2024
Lund University
2010-2024
Technical University of Denmark
2014-2023
Danish Energy Association
2022
University of Washington
2019-2021
Industrial Measurement Systems (United States)
2020
SINTEF
2012
Mechanics' Institute
2003-2011
Ilisimatusarfik
2010
Roskilde University
2010
Abstract Average power losses due to wind turbine wakes are of the order 10 20% total output in large offshore farms. Accurately quantifying is, therefore, an important part overall farm economics. The focus this research is compare different types models from computational fluid dynamics (CFD) terms how accurately they represent wake when compared with measurements ultimate objective improve modelling flow for farms optimize layouts reduce and loads. presented EC‐funded UpWind project,...
ABSTRACT The wind turbine operational characteristics, power measurements and meteorological from Horns Rev offshore farm have been identified, synchronized, quality screened stored in a common database as 10 min statistical data. A number of flow cases identified to describe the inside farm, deficits along rows turbines determined for different inflow directions speed intervals. method classify atmospheric stability based on Bulk‐Ri has implemented. Long‐term conditions established, which...
Abstract There is an urgent need to develop and optimize tools for designing large wind farm arrays deployment offshore. This research focused on improving the understanding of, modeling turbine wakes in order make more accurate power output predictions offshore farms. Detailed data ensembles of losses due at farms Nysted Horns Rev are presented analyzed. Differences spacing (10.5 versus 7 rotor diameters) not differentiable wake-related from two partly high variability despite careful...
Accurately quantifying wind turbine wakes is a key aspect of farm economics in large farms. This paper introduces new simulation post-processing method to address the direction uncertainty present measurements Horns Rev offshore farm. technique replaces traditional simulations performed with 10 min average by weighted several covering wide span directions. The weights are based on normal distribution account for from yaw misalignment reference turbine, spatial variability inside and within...
We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid detector at Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over background-only null hypothesis with greater than $3\ensuremath{\sigma}$ significance. The measured cross section, averaged incident neutrino flux, is $(2.2\ifmmode\pm\else\textpm\fi{}0.7)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}39}\text{ }\text{...
ABSTRACT This paper investigates wake effects on load and power production by using the dynamic meander (DWM) model implemented in aeroelastic code HAWC2. The instationary wind farm flow characteristics are modeled treating turbine wakes as passive tracers transported downstream a meandering process driven low frequent cross‐wind turbulence components. complex is validated comparing simulated measured loads for Dutch Egmond aan Zee consisting of 36 Vestas V90 located outside coast...
ABSTRACT Computational fluid dynamic (CFD) methods are used in this paper to predict the power production from entire wind farms complex terrain and shed some light into wake flow patterns. Two full three‐dimensional Navier–Stokes solvers for incompressible flow, employing k − ϵ ω turbulence closures, used. The turbines modeled as momentum absorbers by means of their thrust coefficient through actuator disk approach. Alternative estimating reference speed calculation tested. work presented...
ABSTRACT The phenomenon of wake interaction between two wind turbines was analysed using the actuator line technique and full unsteady Navier–Stokes computations. Results are presented for varying mutual distances both half situations were considered. Furthermore, simulations carried out at different degrees ambient turbulence intensity representing laminar, offshore onshore conditions. From simulations, main characteristics interacting wakes extracted including averaged velocity fields as...
Abstract The power production of the Lillgrund wind farm is determined numerically using large‐eddy simulations and compared with measurements. In order to simulate realistic atmospheric conditions, pre‐generated turbulence shear are imposed in computational domain. conditions from data extracted a met mast, which was erected prior establishment farm. allocate most wake flow, turbines modeled an actuator disc method where discs domain as body forces for every time step calculated tabulated...
The increasing size of wind turbines, with rotors already spanning more than 150 m diameter and hub heights above 100 m, requires proper modeling the atmospheric boundary layer ( ABL ) from surface to free atmosphere. Furthermore, large farm arrays create their own structure unique physics. This poses significant challenges traditional engineering models that rely on surface‐layer theories simulate flow in around farms. However, adopting an approach offers opportunity better integrate design...
Abstract. Numerical wind resource modelling across scales from the mesoscale to turbine scale is of increasing interest due expansion offshore energy. Offshore farm wakes can last several tens kilometres downstream and thus affect resources a large area. So far, scale-specific models have been developed but it remains unclear how well different model types represent intra-farm wakes, farm-to-farm as wake recovery behind farm. Thus, in present analysis simulation set complexity, fidelity,...
A direct measurement of the helicity dependence total photoabsorption cross section on proton was carried out at MAMI (Mainz) in energy range 200<Eγ<800MeV. The experiment used a 4π detection system, circularly polarized tagged photon beam, and frozen spin target. contributions to Gerasimov-Drell-Hearn sum rule forward polarizability γ0 determined from data are 226±5(stat)±12(syst)μb −187±8(stat)±10(syst)×10−6fm4, respectively, for 200<Eγ<800MeV.Received 13 March...
The paper presents research conducted in the Flow workpackage of EU funded UPWIND project which focuses on improving models flow within and downwind large wind farms complex terrain offshore. main activity is modelling behaviour turbine wakes order to improve power output predictions.
The current paper is concerned with determining the optimal layout of turbines inside large offshore wind farms by means an optimization algorithm. We call this Turbine Positioning Problem. To achieve goal a simulated annealing algorithm has been devised, where three types local search operations are performed recursively until system converges. effectiveness proposed demonstrated on suite real life test cases, including Horns Rev farm. results verified using commercial resource software...
Abstract. The wake of a single wind turbine in complex terrain is analysed using measurements from lidars. A particular focus this analysis the deficit and propagation. Six scanning lidars (three short-range three long-range WindScanners) were deployed during Perdigão 2015 measurement campaign, which took place at double-ridge site Portugal. Several scenarios, including triple- dual-Doppler scans, designed to capture 2 MW located on one ridges. Different displacements are categorized...
The COHERENT experiment is well poised to test sub-GeV dark matter models using low-energy recoil detectors sensitive coherent elastic neutrino-nucleus scattering (CEvNS) in the $\pi$-DAR neutrino beam produced by Spallation Neutron Source. We show how a planned 750-kg liquid argon scintillation detector would place leading limits on scalar light models, over two orders of magnitude mass, for particles through vector and leptophobic portals absence other effects beyond standard model....
Wind energy has for many years been the fastest developing source. This is most easily demonstrated by some numbers. In 2006 a total of about 7.6 GW new wind capacity was installed in Europe, an increase more than 20% over year before. Europe's cumulative power now reached 50 GW. At beginning 2007, European Commission published its strategy, which recommends target share renewable EU 2020. New initiatives have also launched U.S. and Asia to comply with need reduction emissions CO2 create...
The primary control on the magnitude of power losses induced by wind turbine wakes in large farms is hub-height speed via its link to thrust coefficient. Hence, at low moderate speeds (between cut-in and rated speeds) when coefficient high, wake are proportionally larger decrease be virtually undetectable above speeds. Wind direction also critical. Not only does it determine effective spacing between turbines but distribution primarily determined synoptic forcing typically has a predominant...
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...
The recently developed k-ε-fP eddy-viscosity model is applied to one on-shore and two off-shore wind farms.The results are compared with power measurements of the standard k-ε model.In addition, direction uncertainty used correct a Gaussian filter.The underpredicts deficit first downstream turbines, whereas eddyviscosity shows good agreement measurements.However, difference in predicted by turbulence models becomes smaller for turbines that located further downstream.Moreover, between...
The helicity dependence of the single pion photoproduction on proton has been measured in energy range from 200 to 450 MeV for first time. experiment, performed at Mainz microtron MAMI, used a 4π-detector system, circularly polarized, tagged photon beam, and frozen-spin target. data obtained provide new information multipole analyses determine main contributions Gerasimov-Drell-Hearn sum rule forward spin polarizability γ0.Received 6 January...
To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for first time experimentally, we measured helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally nucleons in photon energy range 0.68-1.82 GeV tagged facility at ELSA. The experiment was carried out a 4pi detection system, beam, frozen spin proton target. contribution to GDH this is [49.9+/-2.4(stat)+/-2.2(syst)] microb.
Inclusive cross sections for the proton and nuclear targets of A=4, 9, 12, 16 were measured 537 730 MeV electrons scattered at 37.1 deg. Systematic features continuum scattering data are compared with other electron photoabsorption measurements. A model calculation based on isobar-hole formalism is in delta resonance region.