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Dekkers, Gert (author)The interaction of a turbulent flow with the leading edge of a foil is one of the dominant noise sources for many engineering applications, including aircraft wings, (wind) turbine blades, and non-cavitating marine propellers such as those found on tidal turbines, naval vessels and submarines. Incorporating a better understanding of the...master thesis 2024
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Janoff, Philipp (author)Leading edge roughness is an important challenge for the wind energy industry as blades are permanently exposed to the damaging impacts of the environment. The contamination due to impact of insects, ice accretion and dust; as well as the erosion of the blade due to rain, debris and abrasive airborne particles increase roughness upon the surface...master thesis 2023
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Bouman, Naomi (author)Airborne wind energy systems offer a promising approach for renewable energy generation. However, the noise emissions associated with these systems should be understood and minimized as well to promote their integration and (social) acceptance. This research aims to identify the noise sources of airborne wind energy systems, systems with leading...master thesis 2023
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D'Aguanno, A. (author)The flight envelope of an aircraft operating at high subsonic velocities is bounded by several limitations, one of these consists in thewing experiencing oscillations of a shockwave on its suction side for a certain range ofMach number (Ma), angle of attack (®) and Reynolds number (Re). This phenomenon is referred to as transonic buffet and it...doctoral thesis 2023
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Gutiérrez, R. (author), Zamponi, R. (author), Ragni, D. (author), Llorente, Elena (author), Aranguren, Patricia (author)Modern wind turbines employ thick airfoils in the outer region of the blade with strong adverse pressure gradients and high sensitivity to flow separation, which can be anticipated by leading-edge roughness. However, Reynolds average Navier-Stokes simulations currently overpredict the Reynolds shear stresses near the surface, and the flow...journal article 2023
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Timmer, W.A. (author), Bak, Christian (author)This chapter focuses on airfoils for wind turbine blades and their characteristics. The use of panel codes such as XFOIL and RFOIL and CFD codes for the prediction of airfoil characteristics is briefly described. This chapter then discusses the requirements for wind turbine blade airfoils and the effect of leading edge roughness and Reynolds...book chapter 2023
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Porta i Ko, Agustí (author)Airborne wind energy (AWE) systems benefit from a high lift airfoil to increase the power output, to that end, multi-element airfoils are investigated for AWE applications. This thesis aims to optimize a multi-element airfoil for a rigid AWE kite that operates in a pumping cycle. Since the kite has distinct operational phases, i.e., reel-out and...master thesis 2022
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Kakkar, Samarth (author)The main objective of this thesis was to explore the capabilities of neural networks in terms of representing governing differential equations, primarily in the purview of fluid/aero dynamic flows. The governing differential equations were accommodated within the loss functions for training the neural networks, thereby making them 'physics...master thesis 2022
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Huang, Dobbin (author)Physics-informed machine learning is a novel approach to solving flow problems with physics-informed neural networks (PINNs), that combines physical knowledge and machine learning.<br/>This study aims to investigate the potential of the application of PINNs in fluid mechanics problems by solving two practical flow problems.<br/><br/>The first...master thesis 2022
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Ravi Ramesh, Ravi (author)Airfoils in deep stall have been a subject of extensive computational discussion in the past, with multiple efforts being performed by various institutions to test their solvers and turbulence/hybrid sub-grid scale (SGS) models for their use in massively separated flows. This case has an important application in turbomachinery where unsteady...master thesis 2021
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Zamponi, R. (author)The interaction of an airfoil with incident turbulence is an important source of aerodynamic noise in numerous applications, such as turbofan engines, cooling systems for automotive and construction industries, high-lift devices on aircraft wings, and landing gear systems. In these instances, turbulence is generally produced by elements that are...doctoral thesis 2021
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De Tavernier, D. (author)As wind farms tend to move towards deeper waters with better wind resources, the classical top-heavy horizontal-axis wind turbines (HAWTs) become particularly challenging. This raises the question whether other concepts could be more suitable and compatible with the deep-sea floating conditions. Hence, the interest in vertical-axis wind turbines...doctoral thesis 2021
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Teruna, C. (author), Avallone, F. (author), Casalino, D. (author), Ragni, D. (author)A lattice-Boltzmann method has been employed to study the aeroacoustics and aerodynamics of airfoils equipped with leading edge treatments, namely the porous leading edge and leading edge serrations. The present study aims to identify the differences in noise reduction mechanisms between the two treatments. Within the context of...journal article 2021
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Geuens, C.S.E. (author)Direct design optimisation methods for turbomachinery blades have consistently gained in popularity over time. This has been accomplished by significant advances in optimisation algorithms, and notably the development of adjoint-based gradient computation, which provides objective sensitivity information at comparatively low computational cost....master thesis 2020
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Timmer, W.A. (author)A relatively simple method is presented to predict the maximum two-dimensional drag coefficient of an airfoil only using its shape. The method is based on a contribution related to the leading edge thickness in terms of the y/c coordinate at x/c=0.0125 and a contribution related to the trailing edge flow angle which appears also to be...journal article 2020
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Mazza, Piero (author)This work follows the wind energy airfoil probabilistic design approach that allows to derive a probability density function which gives an estimation of how much the angle of attack is likely to fluctuate, according to the considered non-uniform perturbations in the wind speed. Several combinations of the perturbation sources are possible in...master thesis 2020
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Zamponi, R. (author), Satcunanathan, S. (author), Moreau, S. (author), Ragni, D. (author), Meinke, M. (author), Schröder, W. (author), Schram, C. (author)A possible strategy for the reduction of the aeroacoustic noise generated by turbulence interacting with a wing profile, also referred to as leading-edge noise, is represented by the implementation of a porous medium in the structure of the airfoil. However, the physical mechanisms involved in this noise mitigation technique remain unclear....journal article 2020
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Mertens, C. (author), Wolf, C. Christian (author), Gardner, Anthony D. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author)Advanced data processing methods for detecting unsteady boundary layer transition in periodic aerodynamic processes by means of infrared thermography measurements are presented. The thermal radiation emitted from the heated suction surface of a pitching airfoil model in subsonic flow is measured with an infrared camera. The unsteady boundary...journal article 2020
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De Voogt, Francis (author)Stall is traditionally divided in three types of stall behaviour, these have been regarded as two dimensional and dominated by the airfoil shape. However one of these types of stall behaviour, trailing edge stall, has been shown in literature to be three dimensional by forming stall cells along the wing span. Stall cells are coherent flow...master thesis 2019
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van Pelt, Pieter (author)The Kutta condition is a boundary condition applied at a wing’s trailing edge (TE), which enables the calculation of the fluid-dynamic lift produced by a wing in potential flow. This condition is actually a stable equilibrium resulting from a transient flow. The main question of this research is: how is the Kutta condition flow-field created...master thesis 2019