126 research outputs found
Challenges in Rotor Aerodynamic Modeling for Non-Uniform Inflow Conditions
Within an international collaboration framework, the accuracy of rotor
aerodynamic models used for design load calculations of wind turbines is being assessed. Where
the use of high-fidelity computation fluid dynamics (CFD) and mid-fidelity free-vortex wake
(FVW) models has become commonplace within the wind energy community, these still fail to
meet the requirements in terms of execution time and computational cost needed for design
load calculations. The fast but engineering fidelity blade-element/momentum (BEM) method
can therefore still be considered the industry workhorse for design load simulations.
At the same time, upscaling of wind turbine rotors makes inflow non-uniformities (e.g. shear,
veer, turbulence) more important. The objective of this work is to assess model accuracy in
non-uniform inflow conditions, which violate several BEM assumptions. Thereto a comparison
in turbulent inflow has been executed including a wide variety of codes, focusing on the DanAero
field measurements, where a 2.3-MW turbine was equipped with, among other sensors, a pressure
measurement apparatus. The results indicate that, although average load patterns are in good
agreement, this does not hold for the unsteady loads that drive fatigue damage and aeroelastic stability. A simplified comparison round in vertical shear was initiated to investigate
the observed differences in a more controlled manner. A consistent offset in load amplitude was
observed between CFD and free-vortex codes on the one hand and BEM-type codes on the other
hand. To shed more light on the observations, dedicated efforts are ongoing to pinpoint the cause
for these differences, in the end leading to guidelines for an improved BEM implementation
Comparison of low molecular weight glutenin subunits identified by SDS-PAGE, 2-DE, MALDI-TOF-MS and PCR in common wheat
Low-molecular-weight glutenin subunits (LMW-GS) play a crucial role in determining end-use quality of common wheat by influencing the viscoelastic properties of dough. Four different methods - sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional gel electrophoresis (2-DE, IEF × SDS-PAGE), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and polymerase chain reaction (PCR), were used to characterize the LMW-GS composition in 103 cultivars from 12 countries
Experience with capture cavity II
Valuable experience in operating and maintaining superconducting RF cavities in a horizontal test module has been gained with Capture Cavity II. We report on all facets of our experience to date
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