David Marten

David Marten
Technische Universität Berlin | TUB · Department of Fluid Dynamics and Technical Acoustics

Dr.-Ing.
Development and Application of the QBlade Software, Windenergy Research

About

76
Publications
114,076
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,326
Citations
Additional affiliations
April 2011 - present
Technische Universität Berlin
Position
  • Research Associate

Publications

Publications (76)
Article
Due to the rapid progress in high-performance computing and the availability of increasingly large computational resources, Navier-Stokes computational fluid dynamics (CFD) now offers a cost-effective, versatile and accurate means to improve the understanding of the unsteady aerodynamics of Darrieus wind turbines and deliver more efficient designs....
Article
After almost 20 years of absence from research agendas, interest in the vertical axis wind turbine (VAWT) technology is presently increasing again, after the research stalled in the mid 90's in favor of horizontal axis wind turbines (HAWTs). However, due to the lack of research in past years, there are a significantly lower number of design and cer...
Preprint
Full-text available
Load calculations play a key role in determining the design loads of different wind turbine components. State of the art in the industry is to use the Blade Element Momentum (BEM) theory to calculate the aerodynamic loads. Due to their simplifying assumptions of the rotor aerodynamics, BEM methods have to rely on several engineering correction mode...
Article
When modeling wind turbine wake recovery, the location of wake breakdown plays a crucial role. The breakdown is caused by a rapid deformation of the helical near-wake vortex structure that is triggered by the pairing of successive blade tip vortices. In this paper, the capability of a cost-efficient lifting-line free vortex wake code to accurately...
Thesis
Full-text available
Wind turbines are large and complex machines which operate in a highly unsteady environment. Due to the spatially and temporally stochastic nature of the wind resource, a large amount of simulation data is needed when one wants to assess the lifetime of such a machine. Both extreme events, such as storms, strong gusts or significant wind direction...
Article
Achieving the European Union’s target of 510 GW of installed wind energy capacity by 2030 requires a significant expansion of the currently installed capacity of 255 GW [1] , [2] . As a consequence of these ambitions, the power density of newly developed wind farms is rising by increasing the number of turbines within a wind farm and the size o...
Conference Paper
Full-text available
This paper presents a two-level control scheme for multi-rotor wind turbines. The first subordinate decentralized controller replaces the active pitch control with oversized generators that achieve the power limitation objective. In combination with this, the second higher-level controller mitigates the mechanical load on the main tower by adjustin...
Article
Full-text available
Reference wind turbine designs and the associated aeroelastic models are widely used in both research and industry. Reference models representing future concepts are of particular interest. Current state of the art aeroelastic tools are relied upon to design the next generation of large wind turbines. However, modelling assumptions may be invalidat...
Article
Full-text available
This paper presents a two-level control scheme for multi-rotor wind turbines. The first subordinate decentralized controller replaces the active pitch control with oversized generators that achieve the power limitation objective. In combination with this, the second higher-level controller mitigates the mechanical load on the main tower by adjustin...
Article
Full-text available
Floating offshore wind is widely considered to be a promising technology to harvest renewable energy in deep ocean waters and increase clean energy generation offshore. While evolving quickly from a technological point of view, floating offshore wind turbines (FOWTs) are challenging, as their performance and loads are governed by complex dynamics t...
Article
Full-text available
To realize the projected increase in worldwide demand for floating offshore wind, numerical simulation tools must capture the relevant physics with a high level of detail while being numerically efficient. This allows engineers to have better designs based on more accurate predictions of the design driving loads, potentially enabling an economic br...
Article
Full-text available
This study reports the results of the second round of analyses of the Offshore Code Comparison, Collaboration, Continued, with Correlation and unCertainty (OC6) project Phase III. While the first round investigated rotor aerodynamic loading, here, focus is given to the wake behavior of a floating wind turbine under large motion. Wind tunnel experim...
Preprint
Full-text available
To realize the projected increase in world-wide demand for floating offshore wind, numerical simulation tools must capture the relevant physics with a high level of detail while being numerically efficient. This allows engineers to have better designs based on more accurate predictions of the design driving loads, potentially enabling an economic b...
Preprint
Full-text available
Consensus is arising on considering floating offshore wind as the most promising technologies to increase renewable energy generation offshore. While evolving fast from a technological point of view, Floating Offshore Wind Turbines (FOWTs) are challenging, as their performance and loads are governed by complex dynamics that are a result of the coup...
Article
Full-text available
This paper provides a summary of the work done within Phase III of the Offshore Code Comparison Collaboration, Continued, with Correlation and unCertainty (OC6) project, under the International Energy Agency Wind Technology Collaboration Programme Task 30. This phase focused on validating the aerodynamic loading on a wind turbine rotor undergoing l...
Preprint
Full-text available
This study reports the results of the second round of analyses of the OC6 project Phase III. While the first round investigated rotor aerodynamic loading, here focus is given to the wake behavior of a floating wind turbine under large motion. Wind tunnel experimental data from the UNsteady Aerodynamics for FLOating Wind (UNAFLOW) project are compar...
Technical Report
Full-text available
In work package 2 of the FLOATECH project a detailed validation and verification of the capabilities of QBlade-Ocean is carried out. A detailed description of the models used in the validation is provided in Deliverable 2.1 and results of the validation that was carried out are presented in Deliverable 2.2. Some modifications to the models used in...
Technical Report
Full-text available
This report constitutes deliverable 2.2 of the FLOATECH project, funded under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101007142. For the detailed validation and verification of the capabilities of QBlade-Ocean in work package 2 (WP2) of FLOATECH, a detailed definition of the three considered mod...
Preprint
Full-text available
This paper provides a summary of the work done within Phase III of the Offshore Code Comparison, Collaboration, Continued, with Correlation and unCertainty project (OC6), under International Energy Agency Wind Task 30. This phase focused on validating the aerodynamic loading on a wind turbine rotor undergoing large motion caused by a floating suppo...
Technical Report
Full-text available
This is a snapshot of the QBlade v2.0.4 Documentation. The most recent version of this document can be accessed from: <https://docs.qblade.org>. QBlade is a state of the art multi-physics code, covering the complete range of aspects required for the aero-servo-hydro-elastic simulation of horizontal, or vertical axis wind turbines. QBlade is being d...
Article
Full-text available
Lifting-line based solvers could supersede the blade element momentum (BEM) method as the industry standard in the near future as rotor sizes of modern wind turbines and computational resources continue to increase. A comparison study between both methods is presented where the IEA 10 MW wind turbine is evaluated in the aero-servo-elastic simulatio...
Technical Report
Full-text available
This document is a deliverable of the FLOATECH project, funded under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101007142.
Article
Full-text available
Active trailing edge flaps are a promising technology that can potentially enable further increases in wind turbine sizes without the disproportionate increase in loads, thus reducing the cost of wind energy even further. Extreme loads and critical deflections of the blade are design-driving issues that can effectively be reduced by flaps. In this...
Preprint
Full-text available
Active trailing edge flaps are a promising technology that can potentially enable further increases in wind turbine sizes without the disproportionate increase in loads, thus reducing the cost of wind energy even further. Extreme loads and critical deflections of the blade are design driving issues that can effectively be reduced by flaps. In this...
Article
Full-text available
Accurate and reproducible aeroelastic load calculations are indispensable for designing modern multi-MW wind turbines. They are also essential for assessing the load reduction capabilities of advanced wind turbine control strategies. In this paper, we contribute to this topic by introducing the TUB Controller, an advanced open-source wind turbine c...
Article
Full-text available
A method is presented which aims to bridge the gap between overlysimplified momentum-based wake models and overly demanding finite volume models of wind turbinewake evolution. The method has been developed to allow an essentially user-defined resolutionof the wake. Beyond this, all dominant field quantities are automatically resolved by the solveri...
Article
Full-text available
Load calculations play a key role in determining the design loads of different wind turbine components. To obtain the aerodynamic loads for these calculations, the industry relies heavily on the Blade Element Momentum (BEM) theory. BEM methods use several engineering correction models to capture the aerodynamic phenomena present in Design Load Case...
Article
The evolution of the wake of a wind turbine contributes significantly to its operation and performance, as well as to those of machines installed in the vicinity. The inherent unsteady and three-dimensional (3D) aerodynamics of vertical axis wind turbines (VAWT) have hitherto limited the research on wake evolution. In this paper, the wakes of both...
Article
Thanks to the renewed interest in vertical-axis wind turbines, research efforts are devoted at improving the accuracy of present simulation tools, many of which are underdeveloped if compared to those for horizontal-axis turbines. In particular, recent studies demonstrated that a correction for the “virtual camber” effect has a major impact on the...
Conference Paper
Full-text available
Ice throw and fall analysis using a semi-empirical Monte Carlo approach seems to be a good trade off between empirical formulation and complex full physics simulations. This paper looks at some of the challenges of running these simulations particularly at the uncertainty of certain input data. The field testing so far has helped provide data on a...
Article
Full-text available
In the present paper, numerical and experimental investigations of a model wind turbine with a diameter of 3.0 m are described. The study has three objectives. The first one is the provision of validation data. The second one is to estimate the influence of the wind tunnel walls by comparing measurements to simulated results with and without wind t...
Conference Paper
In the current paper a method to correct cross-talk effects for strain-gauge measurements is presented. The method is demonstrated on an experimental horizontal axis wind turbine. The procedure takes cross-moments (flap-wise on edgewise moments and vice versa) as well as axial acceleration into account. The results from the experimental setup are c...
Conference Paper
This paper presents the results of a fatigue load evaluation from aeroelastic simulations of a multi-megawatt wind turbine. Both the Blade Element Momentum (BEM) and the Lifting Line Free Vortex Wake (LLFVW) methods were used to compute the aerodynamic forces. The loads in selected turbine components, calculated from NREL’s FAST v8 using the aerody...
Conference Paper
A recently formulated model for the treatment of the evolution of the wake of aerodynamic bodies has been implemented into the wind turbine simulation software QBlade with the aim of modelling near and far wake behavior with a so-called medium order model. The paper first presents the vortex particle treatment of the wake. Shed and trailing vortex...
Conference Paper
A method for the treatment of the evolution of the wake of aerodynamic bodies has been implemented. A vortex particle method approach has been used whereby the flow field is discretized into numerical volumes which possess a given circulation. A lifting line formulation is used to determine the circulation of the trailing and shed vortex elements....
Article
Full-text available
The current paper describes an aerodynamic model for treatment of wind turbine wakes. For accurate treatment of the wake evolution for the near wake, along with interaction with local flow features, a model with low numerical diffusion has been chosen, a vortex particle method, which inherently allows treatment also of shearing effects and viscous...
Conference Paper
After almost 20 years of absence from research agendas, interest in the vertical axis wind turbine (VAWT) technology is presently increasing again, after the research stalled in the mid 90's in favour of horizontal axis turbines (HAWTs). However, due to the lack of research in past years, there are a significantly lower number of design and certifi...
Article
Full-text available
The QBlade implementation of the lifting-line free vortex wake (LLFVW) method was tested in conditions analogous to floating platform motion. Comparisons against two independent test cases using a variety of simulation methods show good agreement in thrust forces, rotor power, blade forces and rotor plane induction. Along with the many verification...
Article
Full-text available
Numerical and experimental investigations of a model wind turbine with a diameter of 3.0 m are described in the present paper. The objectives of the study are the provision of validation data, the comparison and evaluation of methods of different fidelity and the assessment of the influence of the wind tunnel walls by comparison of measurements to...
Article
Recently a new interest in vertical axis wind turbine (VAWT) technology is fueled by research on floating support structures for large scale offshore wind energy application. For the application on floating structures at multi megawatt size, the VAWT concept may offer distinct advantages over the conventional horizontal axis wind turbine (HAWT) des...
Conference Paper
The evolution of the wake of a wind turbine contributes significantly to its operation and performance, as well as to those of machines installed in the vicinity. The inherent unsteady and three-dimensional aerodynamics of Vertical Axis Wind Turbines (VAWT) have hitherto limited the research on wake evolution. In this paper the wakes of both a trop...
Conference Paper
Due to the rapid progress in high-performance computing and the availability of increasingly large computational resources, Navier-Stokes computational fluid dynamics (CFD) now offers a cost-effective, versatile and accurate means to improve the understanding of the unsteady aerodynamics of Darrieus wind turbines and deliver more efficient designs....
Conference Paper
Full-text available
The open source simulation code QBLADE, based on a Lifting Line Free Vortex Wake formulation to evaluate the unsteady aerodynamics, recently integrated the PROJECT-CHRONO FEA library that, by using Euler-Bernoulli beams in a corotational formulation, solves for the structural dynamics to achieve an aeroelastic coupling. To validate the newly implem...
Article
Full-text available
The QBlade implementation of the Lifting Line Free Vortex Wake method(LLFVW) was tested in conditions analogous to floating platform motion. Comparisons against two independent test cases, using a variety of simulation methods show excellent agreement in thrust forces, rotor power, blade forces and rotor plane induction. Along with the many verific...
Article
Full-text available
The current paper investigates the aeroelastic modelling of large, flexible multi- MW wind turbine blades. Most current performance prediction tools make use of the Blade Element Momentum (BEM) model, based upon a number of simplifying assumptions that hold only under steady conditions. This is why a lifting line free vortex wake (LLFVW) algorithm...
Article
Full-text available
The QBlade implementation of the Lifting Line Free Vortex Wake method(LLFVW) was tested in conditions analogous to floating platform motion. Comparisons against two independent test cases, using a variety of simulation methods show excellent agreement in thrust forces, rotor power, blade forces and rotor plane induction. Along with the many verific...
Article
Interest in vertical-axis wind turbines (VAWTs) is experiencing a renaissance after most major research projects came to a standstill in the mid 1990s, in favor of conventional horizontal-axis turbines (HAWTs). Nowadays, the inherent advantages of the VAWT concept, especially in the Darrieus configuration, may outweigh their disadvantages in specif...
Conference Paper
A coupling of the Lifting Line Free Vortex Wake (LLFVW) model of the open source wind turbine software QBlade and the wind turbine structural analysis tool FAST has been achieved. FAST has been modified and compiled as a dynamic library, taking rotor blade loading from the LLFVW model as input. Most current wind turbine aeroelastic simulations make...
Conference Paper
This paper describes the introduction of an unsteady aerodynamics model applicable for horizontal and vertical axis wind turbines (HAWT/VAWT) into the advanced blade design and simulation code QBlade, developed at the HFI of the TU Berlin. The software contains a module based on lifting line theory including a free vortex wake algorithm (LLFVW) whi...
Conference Paper
Interest in vertical-axis wind turbines (VAWTs) is experiencing a renaissance after most major research projects came to a standstill in the mid 90’s, in favour of conventional horizontal-axis turbines (HAWTs). Nowadays, the inherent advantages of the VAWT concept, especially in the Darrieus configuration, may outweigh their disadvantages in specif...
Technical Report
Full-text available
This document is an updated version of the “QBlade v0.9 Users Guide”. QBlade v0.95 introduces some new functionality for which additional paragraphs have been added to this document. A dynamic stall model has been implemented which can be used in HAWT & VAWT simulations. Additionally this new version allows assigning multiple polars to blade sectio...
Technical Report
Full-text available
The airfoil TE noise module PNoise was developed under a Poli-USP and TU-Berlin collaboration project. The TE noise module is based on a modified BPM TE noise model (Brooks, et al., 1989) with turbulent boundary layer data provided by XFLR5 (Drela, et al., 2009), both integrated inside the unique wind-turbine-design, graphical interface and user-fr...
Conference Paper
Full-text available
Recently a new interest in vertical axis wind turbine (VAWT) technology is fueled by research on floating support structures for large scale offshore wind energy application. For the application on floating structures at multi megawatt size, the VAWT concept may offer distinct advantages over the conventional horizontal axis wind turbine (HAWT) des...
Article
The development of the next generation of large multi-megawatt wind turbines presents exceptional challenges to the applied aerodynamic design tools. Because their operation is often outside the validated range of current state of the art momentum balance models, there is a demand for more sophisticated, but still computationally efficient simulati...
Conference Paper
Full-text available
Up to now, the main aerodynamic methods used in almost all wind turbine certification calculations are still based on simple blade element momentum theory models (BEM). Regardless of the large number of empirical corrections, which have been added over the years, BEM simulations can introduce inaccuracies in situations where one or more of its inte...
Research
The Guidelines to use the Lifting Line Module in QBlade
Technical Report
Full-text available
This short manual is not intended to give a full overview of the applied simulation methods and their theory. This document is rather meant as a brief guide to enable the users to work with the new version of QBlade and give a short overview of the overall functionality that was implemented in QBlade v0.9. In v0.9 a new module for unsteady aerodyna...
Conference Paper
If the number of suitable sites for horizontal axis wind turbines is limited, increasing the rotor diameter is a viable means of increasing the power output of the wind turbine. For a given wind speed the power output theoretically increases with the radius squared. However, the material needed to upscale a classically designed rotor that withstand...
Conference Paper
The first German active load control research wind turbine is introduces. The setup in a new wind energy wind tunnel test section is presented and the data aquisition system inside the rotating hub is described. Some preliminary measurement and simulation results are shown.
Conference Paper
The development of the next generation of large multi-megawatt wind turbines presents exceptional challenges to the applied aerodynamic design tools. Because their operation is often outside the validated range of current state of the art momentum balance models, there is a demand for more sophisticated, but still computationally efficient simulati...
Conference Paper
To certify a Wind Turbine the standard processes set out by the GL guidelines and the IEC61400 demand a large number of simulations in order to justify the safe operation of the machine in all reasonably probable scenarios. The result of this rather demanding process is that the simulations rely on lower fidelity methods such as the Blade Element M...
Article
Wind turbines are exposed to unsteady incident flow conditions such as gusts or tower interference. These cause a change in the blades' local angle of attack, which often leads to flow separation at the inner rotor sections. Recirculation areas and dynamic stall may occur, which lead to an uneven load distribution along the blade. In this work, a f...
Technical Report
Full-text available
This short manual is not intended to give an overview of the applied simulation methods and their theory. This document is rather meant as a brief guide to enable the users to work with the new version of QBlade and give a short overview of the overall functionality and the new features of v.08.