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Bots, Michiel (author)
Floating offshore wind turbines can only withstand a limited amount of (heave) motions before the equipment fails. In order to reduce the heave motion, the DeepCwind floater for offshore floating wind turbines makes use of heave plates. This semi-submersible floater consists of three cylindrical columns with a heave plate attached to the bottom...
master thesis 2020
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Horck, Mats (author)
Exposure to excessive community noise has become a large environmental health concern. Noise pollution continues to increase while it is accompanied by direct, as well as cumulative adverse health effects. In addition, prolonged exposure to excessive noise levels also has a negative economic impact. The incorporation of numerical tools in the...
master thesis 2020
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Huijing, Jasper (author)
RANS simulation are one of the most used tools for aerodynamic analysis. The advantage of RANS simulations is the reduced computational cost compared to other methods such as LES or DNS. This is because by solving the RANS equations one only solves for the mean flow. However, this reduction in computational cost comes at the price of uncertainty...
master thesis 2020
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Wang, Xiuqi (author)
To realize sustainable development, offshore wind energy has been a highly valuable solution to meet the demand for renewable energy. Accompanied with the construction of the offshore wind turbines, cable casting and the following cable trenching process in the underwater condition are necessarily required. The research on the underwater sand...
master thesis 2020
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Leung, K.C. (author)
A low-speed aerodynamic analysis on the conventional NACA ram-air inlet of the Airbus A320 with a new closure flap was conducted. The conventional closure flap mechanism inside the NACA ram-air inlet is replaced by a morphing plate design. Steady-state Reynolds-Averaged Navier-Stokes (RANS) based Computational Fluid Dynamics (CFD) simulations...
master thesis 2020
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Goderie, Michiel (author)
Wind turbine wakes cause significant reductions in power production and increased fatigue damage for downwind turbines. Thus, they affect the wind levelized cost of energy. Computational Fluid Dynamics (CFD) can be used to quantify the wake characteristics, whereby Reynolds-averaged Navier-Stokes (RANS) has the most potential for industrial...
master thesis 2020
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Karageorgiou, Traianos (author)
The graduation project was conducted at the CFD department of Nuclear Research And Consultancy Group (NRG) in Petten. The modeling and simulation of Taylor bubble flow using CFD can contribute significantly to the topic of nuclear reactor safety and in particular, in the emergency cooling of nuclear reactors during a loss of coolant accident, or...
master thesis 2020
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Opsomer, Aviva (author)
Rising temperatures due to climate change and the increased Urban Heat Island (UHI) effect both have a major impact on Singapore’s outdoor comfort. Research has reported an average UHI in Singapore of 4°C, which can even exceed 7°C at some times of the day. (Acero & Ruefenacht, 2017) Increasing convective surface heat transfer from the human...
master thesis 2020
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Dammers, Tim (author)
Lean premixed flames are being used in gas turbines to reduce the emission of NOx. Unfortunately, it results often in thermoacoustic instabilities. These instabilities are high amplitude pressure oscillations which cause damage to the combustion system, reduce efficiency, flame blow-off or flashback. While the cause for instabilities due to...
master thesis 2020
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Pal, Somnath (author)
The total electrical energy consumption by all the operational data centers (located all over the world) is enormous (approx. 1% of the global electricity demand 20000TWh). This electrical energy is required 24x7 to operate and cool all the IT equipment present in the data center. The electrical energy required to cool all...
master thesis 2020
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Bierhuizen, Luc (author)
Due to the presence of a monopile in a turbulent flow swirling vortices, known as horseshoe vortices, can form upstream of the structure near the cylinder-bed junction. Those vortices then travel downstream of the cylinder as they are being dragged along with the current. The horseshoe vortices can scoop up bed material surrounding the cylinder,...
master thesis 2020
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Barfknecht, Nils (author)
Computational fluid dynamics (CFD) has become an indispensable tool in research and engineering. Even though the performance of computers is increasing at unfathomable speeds, the calculation of many fluid problems remains to be challenging. With the emerging widespread use of Large Eddy Simulation (LES), the computational cost of simulations...
master thesis 2020
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Boatto, Umberto (author)
Accurate aerodynamic and aeroacoustic simulations of helicopters and wind turbines require the inclusion of the blade elasticity into the computational setup. If low-order aerodynamic models can be efficient for optimization purposes, they are often insufficient in predicting the complex flow phenomena responsible for structural vibrations and...
master thesis 2020
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Ankith John Santosh, Ankith (author)
In order to meet the growing market demands of quieter, more aerodynamically efficient aircrafts, manufacturers constantly strive to innovate and optimize their designs. Over the years however, the extent of innovation related to the conventional 'tubular fuselage' configurations have somewhat reached a stalemate as the gains obtained have only...
master thesis 2020
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Ballapur Jayasimha, Athreya (author)
Horizontal Axis Wind Turbines (HAWTs) are a very popular source of renewable energy, but these machines are often subject to off-design conditions owing to the unsteady nature of wind. Unsteady aerodynamic conditions have been associated with cyclic loading of turbine blades, which can have hugely detrimental effects on their operational life....
master thesis 2020
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Luan, Yuyang (author)
In studies of wind plant designs, wake dynamics are of great interests as wakes affect downstream turbine loading that impacts wind plant efficiency. Recent developments of Tensor Basis Decision Tree (TBDT) based machine learning (ML) models in reconstructing the turbulence anisotropy fields of simple flow cases prompt the motivation in applying...
master thesis 2020
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Sprong, Geert (author)
The bulbous bow is a common feature for large displacement vessels. The purpose of the bulbous bow is to reduce the bow wave, hereby making use of wave cancellation theory. The main drawback of these type of bows is that the drag reduction effect is only present for a limited range of sailing speeds. If the transit velocity is altered, the...
master thesis 2019
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Rietema, Roald (author)
Recent decades, an ongoing trend has emerged in the upscaling of wind turbines in order to compete with traditional energy resources. For conventional wind turbines, aside from improving safety, the driving factors for new designs have always been increased efficiency and performance. This has led to novel wind turbine designs comprising thin...
master thesis 2019
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Feij, Christiaan (author)
The case of the flow around a rotating circular cylinder is very complex. This thesis investigates the properties of a fluid flow for Reynolds numbers ranging from 50 to 400. Numerical simulations are performed using a combination of isogeometric analysis and the residual-based variational multiscale method, providing high accuracy. The results...
master thesis 2019
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Wagemans, Tom (author)
In a effort to curb climate change, more and more countries are adding solar and wind farms to their electrical grid. These solar and wind farms produce electrical energy based on environmental conditions, for example solar irradiation intensity or wind speed. As such these farms create fluctuations in the electrical grid and create a mismatch...
master thesis 2019
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