- document
-
Hur, C. (author), Ferreira, Carlos (author), Schepers, Gerard (author)Horizontal axis wind turbines (HAWTs) experience yaw misalignments due to the physical limitations of yaw controllers and various novel active yaw controls. Moreover, the motion of floating offshore wind turbines (FOWTs) accelerates yaw misalignment. The blade element momentum (BEM) method is widely used due to its computational efficiency for...journal article 2022
- document
-
Brandetti, L. (author), Liu, Y. (author), Mulders, S.P. (author), Ferreira, Carlos (author), Watson, S.J. (author), van Wingerden, J.W. (author)In recent years, industrial controllers for modern wind turbines have been designed as a combined wind speed estimator and tip-speed ratio (WSE-TSR) tracking control scheme. In contrast to the conventional and widely used Kω 2 torque control strategy, the WSE-TSR scheme provides flexibility in terms of controller responsiveness and...journal article 2022
- document
-
LeBlanc, B.P. (author), Ferreira, Carlos (author)This paper presents the flow fields and aerodynamic loading of a two bladed H-type vertical axis wind turbine with active variable pitch for load and circulation control. Particle Image Velocimetry is used to capture flow fields at six azimuthal positions of the blades during operation, three upwind and three downwind. Flow phenomena such as...journal article 2021
- document
-
Ferreira, P. (author), Rigotti Manesco, A.L. (author), Dorini, T. T. (author), Correa, L. E. (author), Weber, G. (author), Machado, A. J.S. (author), Eleno, L. T.F. (author)In the present work, we investigate the electronic and elastic properties in equilibrium and under strain of the type-II Dirac semimetal NiTe2 using density functional theory. Our results demonstrate the tunability of Dirac nodes' energy and momentum with strain and that it is possible to bring them closer to the Fermi level, while other...journal article 2021
- document
-
van Kessel, C.L. (author), Bauer, P. (author), Ferreira, Jan Abraham (author)Dielectric elastomer transducers (DETs) are commonly modeled by lumped-element models (LEMs), however such models do not capture the cutoff behavior that manifests at relatively low frequencies due to the high resistivity of the stretchable electrodes. Moreover, the contribution of the electrodes into the lumped series resistance is not...journal article 2021
- document
-
De Tavernier, D. (author), Ferreira, Carlos (author), Viré, A.C. (author), LeBlanc, B.P. (author), Bernardy, S. (author)Vortex generators (VGs) have proven their capabilities in wind turbine applications to delay stall in steady flow conditions. However, their behaviour in unsteady conditions is insufficiently understood. This paper presents an experimental study that demonstrates the effect of VGs in unsteady flow, including controlling and suppressing the...journal article 2021
- document
-
Ferreira, Pedro L. (author), Santos, Francisco C. (author), Gonçalves Melo Pequito, S.D. (author)What humans do when exposed to uncertainty, incomplete information, and a dynamic environment influenced by other agents remains an open scientific challenge with important implications in both science and engineering applications. In these contexts, humans handle social situations by employing elaborate cognitive mechanisms such as theory of...journal article 2021
- document
-
Melani, P. F. (author), Balduzzi, F. (author), Brandetti, L. (author), Ferreira, Carlos (author), Bianchini, A. (author)Simulation methods ensuring a level of fidelity higher than that of the ubiquitous Blade Element Momentum theory are increasingly applied to VAWTs, ranging from Lifting-Line methods, to Actuator Line or Computational Fluid Dynamics (CFD). The inherent complexity of these machines, characterised by a continuous variation of the angle of attack...journal article 2020
- document
-
De Tavernier, D. (author), Ferreira, Carlos (author), Paulsen, U. (author), Madsen, H. (author)This paper deals with the 3D effects of a vertical-axis wind turbine caused by the tip vortices. In this study, the VAWT rotor is simplified by the infinitely bladed actuator cylinder concept. The loads are prescribed to be uniform and normal to the surface and are distributed between the upwind and downwind half. Depending on the load...journal article 2020
- document
-
Brandetti, L. (author), De Tavernier, D. (author), LeBlanc, B.P. (author), Ferreira, Carlos (author)The paper presents an experimental study of applying variable loads on a vertical-axis wind turbine (VAWT). The experiment is conducted in an open-jet wind tunnel on a two-bladed Darrieus VAWT equipped with active individual blade pitch control. Variable loads are achieved by dynamically changing the pitch angle of the individual blades and...journal article 2020
- document
-
De Tavernier, D. (author), Ferreira, Carlos (author)This paper presents a new dynamic inflow model for vertical-axis wind turbines (VAWTs). The model uses the principle of Duhamel's integral. The indicial function of the inflow- and crossflow-induction required to apply Duhamel's integral is represented by an exponential function depending on the thrust coefficient and the azimuthal position....journal article 2020
- document
-
De Tavernier, D. (author), Viré, A.C. (author), Ferreira, Carlos (author)In this work, we demonstrate to what extent it is possible to use load optimisation to aerodynamically damp the floater motion of vertical-axis wind turbines. The loadform of a VAWT can be altered to the desired objective using an individual blade-pitch schedule. A coupled hydro- and aerodynamic simulation tool is built solving the equation...journal article 2020
- document
-
Hou, F. (author), Wang, Qidong (author), Chen, Min (author), Zhang, Kouchi (author), Ferreira, Jan Abraham (author), Wang, Wenbo (author), Ma, R. (author), Su, Meiying (author), Song, Yang (author)In this article, a novel fan-out panel-level printed circuit board (PCB)-embedded package for phase-leg silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) power module is presented. Electro-thermo-mechanical co-design was conducted, and the maximum package parasitic inductance was found to be about 1.24 nH at 100...journal article 2020
- document
-
De Tavernier, D. (author), Sakib, M. (author), Griffith, D.T. (author), Pirrung, G. (author), Paulsen, U. (author), Madsen, H. (author), Keijer, W. (author), Ferreira, Carlos (author)Since the first commercial projects, the development of vertical-axis wind turbines (VAWTs) has been impeded by the limited understanding and inability to accurately model VAWTs. This paper investigates and compares different aerodynamic modelling techniques for VAWTs in 3D. All considered models are using the same blade-element...journal article 2020
- document
-
LeBlanc, B.P. (author), Ferreira, Carlos (author)A digital twin can be described as a digital replica of a physical asset. The use of such models is key to understanding complex loading phenomena experienced during testing of vertical axis wind turbines. Unsteady aerodynamic and structural effects such as dynamic stall and dynamically changing thrust and blade loading are difficult to...journal article 2020
- document
-
Hou, F. (author), Zhang, Hengyun (author), Huang, Dezhu (author), Fan, J. (author), Liu, Fengman (author), Lin, Tingyu (author), Cao, Liqiang (author), Fan, Xuejun (author), Ferreira, Braham (author), Zhang, Kouchi (author)In this article, a microchannel thermal management system (MTMS) with the two-phase flow using the refrigerant R1234yf with low global warming potential is presented. The thermal test vehicles (TTVs) were made of either single or multiple thermal test chips embedded in the substrates, which were then attached to the MTMS. The system included...journal article 2020
- document
-
Cavadas, Joana (author), Azevedo, Carlos Lima (author), Farah, H. (author), Ferreira, Ana (author)Observed accidents have been the main resource for road safety analysis over the past decades. Although such reliance seems quite straightforward, the rare nature of these events has made safety difficult to assess, especially for new and innovative traffic treatments. Surrogate measures of safety have allowed to step away from traditional...journal article 2020
- document
-
LeBlanc, B.P. (author), Ferreira, Carlos (author)The aerodynamic loading of a vertical axis wind turbine varies with the azimuth position of the blades. The thrust of the VAWT can be computed as a decomposition of the normal force on each of the blades. By varying the blade loading as a function of turbine azimuth, it is possible to vary the direction of the average thrust of the turbine....journal article 2020
- document
-
Huang, M. (author), Ferreira, Carlos (author), Sciacchitano, A. (author), Scarano, F. (author)Wind tunnel experiments on a scaled vertical axis wind turbine (VAWT) and square porous plate with a porosity of 64% are conducted in the W-tunnel of TU-Delft. The VAWT thrusts in axial and lateral directions are measured with an in-house load cell system based on moment conservation. Wake of the VAWT in tip speed ratio of 1.5 and 2.5 and the...journal article 2020
- document
-
Bhattacharyya, A. (author), Ferreira, P. P. (author), Santos, F. B. (author), Adroja, D. T. (author), Lord, J. S. (author), Correa, L. E. (author), MacHado, A. J.S. (author), Rigotti Manesco, A.L. (author), Eleno, L. T.F. (author)In this Rapid Communication, we have examined the superconducting ground state of the HfV2Ga4 compound using resistivity, magnetization, zero-field (ZF), and transverse-field (TF) muon-spin relaxation and rotation (μSR) measurements. Resistivity and magnetization unveil the onset of bulk superconductivity with TC∼3.9 K. TF-μSR measurements...journal article 2020