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Gerard van Bussel

Gerard van Bussel
Delft University of Technology faculy Aerospace Engineering · AWEP Aerodynamics Wind Energy Flight Performance & Propulsion

PhD

About

214
Publications
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6,709
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Publications

Publications (214)
Article
Full-text available
Ducted wind turbines (DWTs) can be used for energy harvesting in urban areas where non-uniform flows are caused by the presence of buildings or other surface discontinuities. For this reason, the aerodynamic performance of DWTs in yawed-flow conditions must be characterized depending upon their geometric parameters and operating conditions. A numer...
Article
Full-text available
Micro wind turbines can be structurally integrated on top of the solid base of noise barriers near highways. A number of performance factors were assessed with holistic experiments in wind tunnel and in the field. The wind turbines underperformed when exposed in yawed flow conditions. The theoretical cosθ theories for yaw misalignment did not alway...
Article
Full-text available
Airborne wind energy systems often use kites made of thin membranes to save material costs and increase mobility. However, this design choice increases the complexity of the aeroelastic behaviour of the system and demands high-fidelity tools. On the aerodynamic side of the multi-physics problem, it is quite challenging to create a high quality body...
Article
Purpose When simulating fluid-structure interaction (FSI), it is often essential that the no-slip condition is accurately enforced at the wetted boundary of the structure. This paper aims to evaluate the relative strengths and limitations of the penalty and Lagrange multiplier methods, within the context of modelling FSI, through a comparative anal...
Article
Full-text available
This paper assesses wind resource characteristics and energy yield for micro wind turbines integrated on noise barriers. An experimental set-up with sonic anemometers placed on top of the barrier in reference positions is realized. The effect on wind speed magnitude, inflow angle and turbulence intensity is analysed. The annual energy yield of a mi...
Article
Full-text available
A novel approach is proposed to reduce, compared with the conventional binning approach, the large number of aeroelastic code evaluations that are necessary to obtain equivalent loads acting on wind turbines. These loads describe the effect of long‐term environmental variability on the fatigue loads of a horizontal‐axis wind turbine. In particular,...
Article
Full-text available
Ducted Wind Turbines (DWTs) can be used for energy harvesting in urban areas where non-uniform inflows might be the cause of aerodynamic and acoustic performance degradation. For this reason, an aerodynamic and aero-acoustic analysis of DWTs in yawed inflow condition is performed for two duct geometries: a baseline commercial DWT model, DonQi, and...
Article
Full-text available
A novel immersed boundary method based on a domain decomposition approach is proposed in the context of a finite element discretisation method. It is applicable to incompressible flows past rigid, deforming, or moving bodies. In this method, unlike most immersed boundary methods, strong boundary conditions are imposed in the regions of the computat...
Conference Paper
A modified free-wake vortex ring model is proposed to compute the dynamics of a floating horizontal-axis wind turbine. The model is divided into two parts. The near wake model uses a blade bound vortex model and trailed vortex model, which is developed based on vortex filament method. By contrast, the far wake model is based on the vortex ring meth...
Article
Full-text available
The complex aerodynamic interactions between the rotor and the duct has to be accounted for the design of ducted wind turbines (DWTs). A numerical study to investigate the characteristics of flow around the DWT using a simplified duct-actuator disc (AD) model is carried out. Inviscid and viscous flow calculations are performed to understand the eff...
Article
Full-text available
A modified free-wake vortex ring model is proposed to compute the dynamics of a floating horizontal-axis wind turbine, which is divided into two parts. The near wake model uses a blade bound vortex model and trailed vortex model, which is developed based on vortex filament method with straight lifting lines assumption. By contrast, the far wake mod...
Article
Full-text available
Ducted Wind Turbines (DWTs) can be used for energy harvesting in urban areas where non-uniform flows are caused by the presence of buildings or other surface discontinuities. For this reason, the aerodynamic performance of DWTs in yawed flow conditions must be characterized. A numerical study to investigate the characteristics of flow around two DW...
Article
Full-text available
Multi-element ducts are used to improve the aerodynamic performance of ducted wind turbines (DWTs). Steady-state, two-dimensional computational fluid dynamics (CFD) simulations are performed for a multi-element duct geometry consisting of a duct and a flap; the goal is to evaluate the effects on the aerodynamic performance of the radial gap length...
Preprint
Full-text available
A modified free-wake vortex ring model is proposed to compute the dynamics of a floating horizontal-axis wind turbine. The model is divided into two parts. The near wake model uses a blade bound vortex model and trailed vortex model, which is developed based on vortex filament method. By contrast, the far wake model is based on the vortex ring meth...
Article
Full-text available
Multi-element ducts are used to improve the aerodynamic performance of ducted wind turbines (DWTs). Steady-state, two-dimensional computational fluid dynamics (CFD) simulations are performed for a multi-element duct geometry, consisting of a duct and a flap; goal is to evaluate the effects on the aerodynamic performance of the radial gap length and...
Chapter
Full-text available
The present study aims at providing experimental performance analysis of ducted wind turbines (DWTs) through momentum theory. To simplify the DWT model, a screen emulating the rotor is adopted by applying the actuator disc theory. Two duct models and five different screens are employed for different configurations to investigate the aerodynamic per...
Preprint
Full-text available
A novel approach is proposed to reduce, compared to the conventional binning approach, the large number of aeroelastic code evaluations that are necessary to obtain equivalent loads acting on wind turbines. These loads describe the effect of long-term environmental variability on the fatigue loads of a horizontal-axis wind turbine. In particular De...
Article
Full-text available
To advance the design of a multimegawatt vertical‐axis wind turbine (VAWT), application‐specific airfoils need to be developed. In this research, airfoils are tailored for a VAWT with variable pitch. A genetic algorithm is used to optimise the airfoil shape considering a balance between the aerodynamic and structural performance of airfoils. At rot...
Preprint
Full-text available
For the purpose of uncertainty propagation a new quadrature rule technique is proposed that has positive weights, has high degree, and is constructed using only samples that describe the probability distribution of the uncertain parameters. Moreover, nodes can be added to the quadrature rule, resulting into a sequence of nested rules. The rule is c...
Article
Full-text available
Urban wind energy research is crucial for the success or failure of wind turbines installed in the built environment. Research in this field is fragmented into various research groups working on different topics in isolation with seemingly few efforts of integrating the various fields. This review aims at highlighting the synergies between the vari...
Poster
Full-text available
This paper reports an experimental investigation on the effect of the duct geometry on the aerodynamic performance of an aerofoil shaped ducted wind turbine (DWT). The tested two-dimensional model is composed of an aerofoil equipped with pressure taps and a uniform porous screen. The experimental setup is based on the assumption that the duct flow...
Article
Full-text available
This paper reports an experimental investigation on the effect of the duct geometry on the aerodynamic performance of an aerofoil shaped ducted wind turbine (DWT). The tested two-dimensional model is composed of an aerofoil equipped with pressure taps and a uniform porous screen. The experimental setup is based on the assumption that the duct flow...
Article
Full-text available
This paper aims to study the aerodynamic performance of ducted wind turbines (DWT) using inviscid and viscous flow calculations by accounting for the mutual interaction between the duct and the rotor. Two generalized duct cross section geometries are considered while the rotor is modelled as an actuator disc with constant thrust coefficient. The an...
Article
Full-text available
During the design phase of an offshore wind turbine, it is required to assess the impact of loads on the turbine life time. Due to the varying environmental conditions, the effect of various uncertain parameters has to be studied to provide meaningful conclusions. Incorporating such uncertain parameters in this regard is often done by applying binn...
Article
Full-text available
The IEC standards prescribe an inflow wind field based on models with empirical assumptions to perform load calculations. The use of preview wind speed measurements using nacelle-mounted Lidars allows mitigation of structural loads by suggesting appropriate control action. This relationship is affected by uncertainty in site conditions and the dyna...
Conference Paper
Full-text available
This paper reports an experimental investigation on the effect of the duct geometry on the aerodynamic performance of an aerofoil shaped ducted wind turbine (DWT). The tested two-dimension model is composed of an aerofoil equipped with pressure taps and a uniform porous screen. The experimental setup is based on the assumption that the duct flow is...
Article
Full-text available
Passive vane–type vortex generators (VGs) are commonly used on wind turbine blades to mitigate the effects of flow separation. However, significant uncertainty surrounds VG design guidelines. Understanding the influence of VG parameters on airfoil performance requires a systematic approach targeting wind energy‐specific airfoils. Thus, the 30%‐thic...
Poster
Full-text available
This research aims to study the aerodynamic performance of ducted wind turbines (DWT) using inviscid and viscous flow calculations by accounting for the mutual interaction between the duct and the rotor. A generalized duct cross section geometry is considered while the rotor is modelled as an actuator disc with constant thrust coefficient. The anal...
Preprint
Full-text available
An efficient algorithm is proposed for Bayesian model calibration, which is commonly used to estimate the model parameters of non-linear, computationally expensive models using measurement data. The approach is based on Bayesian statistics: using a prior distribution and a likelihood, the posterior distribution is obtained through application of Ba...
Article
Full-text available
The paper provides a brief overview of the aims and main results of IEA Wind Task 33. IEA Wind Task 33 was an expert working group with a focus on data collection and reliability assessment for O&M optimization of wind turbines. The working group started in 2012 and finalized the work in 2016. The complete results of IEA Wind Task 33 are described...
Technical Report
Full-text available
The implementation of a simplified wake model based on the actuator disc (AD) concept is used to blind benchmark the wind tunnel experiments. This is done using Reynolds averaged Navier-Stokes (RANS) equation in the computational fluid dynamics code FLUENT. Four different turbulence closure models are systematically compared to determine their adeq...
Article
Full-text available
This paper aims to provide an explanation for the overprediction of aerodynamic loads by CFD compared to experiments for the MEXICO wind turbine rotor and improve the CFD prediction by considering laminar-turbulent transition modeling. Large deviations between CFD results and experimental measurements are observed in terms of sectional normal and t...
Article
This paper presents a numerical investigation of transitional flow on the wind turbine airfoil DU91-W2-250 with chord-based Reynolds number Rec = 1.0 × 10⁶. The Reynolds-averaged Navier–Stokes based transition model using laminar kinetic energy concept, namely the k − kL − ω model, is employed to resolve the boundary layer transition. Some ambiguit...
Technical Report
Full-text available
A detailed statistical analysis of the reliability characteristics of systems, components and subassemblies is required to improve the reliability of wind assets. This must be complemented by qualitative assessments of operational and maintenance information sources. Guidelines on how to undertake these tasks will support existing initiatives deali...
Article
In this research the diabatic surface layer wind shear model is extended for offshore wind energy purposes to higher altitudes based on Gryning's wind profile and the resistance functions proposed by Byun. The wind profile is in theory applicable up to the boundary layer height, which is parametrized with the Rossby-Montgommery equation. The coeffi...
Conference Paper
Full-text available
In this paper, a numerical investigation on the effect of gurney flap (GF) on the performance of a diffuser augmented wind turbine (DAWT) is presented. The flow-field around the DAWT is obtained by solving the Reynolds-averaged-Navier-Stokes (RANS) equations. The turbine is modelled as an uniformly loaded actuator disc (AD) that imposes a resistanc...
Conference Paper
A variable stiffness composite optimization framework for wind turbine rotor blades is presented. The framework consists of a multi-fidelity approach for wind turbine rotor analysis, where both structural and aerodynamic constraints are considered during the optimization. The potential of twist coupled blades to regulate the power on stall controll...
Article
Full-text available
This study presents an experimental investigation on a diffuser augmented wind turbine (DAWT). A screen mesh is used to simulate the energy extraction mechanisms of a wind turbine in experiment. Different screen porosities corresponding to different turbine loading coefficients are tested. Measurements of the axial force and of the velocity distrib...
Article
Full-text available
In this paper, a computational approach, based on the solution of Reynolds-averaged-Navier–Stokes (RANS) equations, to describe the flow within and around a diffuser augmented wind turbine (DAWT) is reported. In order to reduce the computational cost, the turbine is modeled as an actuator disc (AD) that imposes a resistance to the passage of the fl...
Article
In recent years there has been a growing interest by the wind energy community to assess the impact of atmospheric stability on wind turbine performance, however up to now, typically, stability is considered in several distinct arbitrary stability classes. As a consequence, each stability class considered still covers a wide range of conditions. In...
Chapter
The reliability of modern onshore wind turbines is at present at an acceptable level. This means that, assuming 100 % site accessibility and implementing a well-organised efficient maintenance strategy, most onshore wind turbines show availability levels of above 98 %. In other words the yearly downtime due to service and repair is less than 1 week...
Article
Full-text available
This paper presents the experimental and numerical study on MEXICO wind turbine blades. Previous work by other researchers shows that large deviations exist in the loads comparison between numerical predictions and experimental data for the rotating MEXICO wind turbine. To reduce complexities and uncertainties, a non-rotating experimental campaign...
Article
Full-text available
Lidars have become increasingly useful for providing accurate wind speed measurements in front of the wind turbine. The wind field measured at distant meteorological masts changes its structure or was too distorted before it reaches the turbine. Thus, one cannot simply apply Taylor's frozen turbulence for representing this distant flow field at the...
Article
Full-text available
In this work, we present a simple inviscid point vortex model to study the dynamics of asymmetric vortex rows, as might appear behind misaligned vortex generator vanes. Starting from the existing solution of the infinite vortex cascade, a numerical model of four base-vortices is chosen to represent two primary counter-rotating vortex pairs and thei...
Article
Full-text available
The article seeks to unify the treatment of conservative force interactions between axi-symmetric bodies and actuators in inviscid flow. Applications include the study of hub interference, diffuser augmented wind turbines and boundary layer ingestion propeller configurations. The conservation equations are integrated over infinitesimal streamtubes...
Article
In this paper we report the results of a workshop organised by the Delft University of Technology in 2014, aiming at the comparison between different state-of-the-art numerical models for the simulation of wind turbine wakes. The chosen benchmark case is a wind tunnel measurement, where stereoscopic Particle Image Velocimetry was employed to obtain...
Conference Paper
Full-text available
ZigZag stripe is an effective tool to artificially trigger flow transition at fixed position when measuring aerodynamic characteristics of airfoils or wind turbine rotor performance in wind tunnel test. In this paper, the influence of ZigZag stripe on wind turbine aerodynamic loads is investigated by analysis of several wind tunnel experimental res...
Article
Full-text available
The root flow of wind turbine blades is subjected to complex physical mechanisms that influence significantly the rotor aerodynamic performance. Spanwise flows, the Himmelskamp effect, and the formation of the root vortex are examples of interrelated aerodynamic phenomena that take place in the blade root region. In this study we address those phen...
Poster
Full-text available
The poster is invitation for assessing the potential of natural earth observation flows to calibrate turbulence models used in the wind energy industry.
Article
A framework based on isogeometric analysis is presented for parametrizing a wind turbine rotor blade and evaluating its response. The framework consists of a multi-fidelity approach for wind turbine rotor analysis. The aeroelastic loads are determined using a low-fidelity model. The model is based on isogeometric approach to model both the structur...
Article
The 3D dynamics of the near wake of a vertical axis wind turbine is simulated by a numerical model based on a free vortex wake/panel method. The model is first verified with respect to discretization sensitivity, stability and robustness. Results show little sensitivity to the discretization, requiring a medium spatial and temporal grid to reach co...
Article
Full-text available
The actuator disc (AD) model is commonly used to simplify the simulation of horizontal-axis wind-turbine aerodynamics. The limitations of this approach in reproducing the wake losses in wind farm simulations have been proven by a previous research. The present study is aimed at providing an experimental analysis of the near-wake turbulent flow of a...
Article
Full-text available
Wind turbine upscaling is motivated by the fact that larger machines can achieve lower levelized cost of energy. However, there are several fundamental issues with the design of such turbines, and there is little public data available for large wind turbine studies. To address this need, we develop a 20 MW common research wind turbine design that i...
Poster
Full-text available
The use of diffusers or ducts to enhance the performance of wind and tidal turbines have been proposed and discussed for many years now. The basic idea is that the presence of a diffuser increases the mass flow across the blades, thus generating more thrust. Some independent studies, using primarily computational fluid dynamics (CFD), suggest a sub...
Article
Full-text available
The European Academy of Wind Energy (eawe), representing universities and institutes with a significant wind energy programme in 14 countries, has discussed the long-term research challenges in wind energy. In contrast to research agendas addressing short- to medium-term research activities, this eawe document takes a longer-term perspective, addre...
Article
Full-text available
The root flow of wind turbine blades is subjected to complex physical mechanisms that influence significantly the rotor aerodynamic performance. Spanwise flows, the Himmelskamp effect and the formation of the root vortex are examples of interrelated aerodynamic phenomena observed in the blade root region. In this study we address those phenomena by...
Article
Full-text available
Kinetic-energy transport and turbulence production within the shear layer of a horizontal-axis wind-turbine wake are investigated with respect to their influence on the tip-vortex pairwise instability, the so-called leapfrogging instability. The study quantifies the effect of near-wake instability and tip-vortex breakdown on the process of mean-flo...
Article
The tip vortex of a wind turbine rotor blade is the result of a distribution of aerodynamic loads and circulation over the blade tip. The current knowledge on the generation of the tip vorticity in a 3D rotating environment still lacks detailed experimental evidence, particularly for yawed flow. The aim of this paper is to investigate how circulati...
Conference Paper
This paper presents a numerical simulation of non-rotating MEXICO blade by using both Reynolds-averaged Navier-Stokes (RANS) and delayed detached-eddy simulation (DDES) approaches in OpenFOAM. Our objective is to investigate the improvement of DDES calculations, compared to RANS calculations when the flow has massive separation. First, DDES concept...
Conference Paper
This paper details an experimental investigation of submerged vane-type vortex generators (VGs) on a flat plate turbulent boundary layer inside a boundary layer wind tunnel. Spanwise planes at various positions downstream of the VG trailing edges are measured using stereoscopic particle image velocimetry (SPIV). The analysis focuses on the streamwi...
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