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van Ede, Matthijs (author)Classical RANS (Reynolds-Averaged Navier-Stokes) turbulence models have limited accuracy in the prediction of the flow over the wing-body geometry. Therefore, this work focuses on improving the prediction accuracy of the classical k-ω SST turbulence model for the junction flow by means of the data-driven method SpaRTA. In the SpaRTA methodology...master thesis 2023
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Zou, P. (author), Kim, Taeksang (author), Bricker, J.D. (author), Uijttewaal, W.S.J. (author)The modelling of complex free surface flows is challenging due to the mobility and deformability of the interface and air entrainment characteristics, which are highly affected by turbulence. With the framework of Reynolds averaged Navier–Stokes (RANS) models and the volume of fluid (VOF) method, turbulence quantities at the air–water...journal article 2023
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van Leeuwen, Elske (author)Computational Fluid Dynamics (CFD) is the main tool to use in industry and engineering problems including turbulent flows. Turbulence modeling relies on solving the Navier-Stokes equations. Solving these equations directly takes a lot of time and computational power. More affordable methods solve the Reynolds Averaged Navier-Stokes (RANS)...master thesis 2022
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Fehrs, Michael (author), Ritter, Markus (author), Helm, Sebastian (author), Mertens, C. (author)The Pazy Wing test case is a benchmark for the investigation of aeroelastic effects at very large deflections. Tip deformations in the order of 50% span were measured in wind tunnel tests, which renders this model highly attractive for the validation of numerical aeroelastic methods and tools for geometrically nonlinear, large deflection...conference paper 2022
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Steiner, J. (author), Dwight, R.P. (author), Viré, A.C. (author)The state-of-the-art in wind-farm flow-physics modeling is Large Eddy Simulation (LES) which makes accurate predictions of most relevant physics, but requires extensive computational resources. The next-fidelity model types are Reynolds-Averaged Navier–Stokes (RANS) which are two orders of magnitude cheaper, but resolve only mean quantities...journal article 2022
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van Alderwegen, Earvin (author)Large-scale measures within the river programmes such as Room for the River, Natura2000 and Water Framework Directive have increased the biodiversity in Dutch rivers and have achieved a more natural landscape. However, recent river programmes have shown conflicts between safety against flooding and riverine nature rehabilitation with maintaining...master thesis 2021
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Gopalan Jayashankar, Gopalan (author)Multiphase flows are very common in many Nuclear engineering applications. During high pressurized conditions there are possibilities of high thermal loads on the pressure vessel, leading to pipe ruptures. As part of breakdown measures, the emergency core cooling system is activated and the coolant is mixed with the fluid in the cold leg, giving...master thesis 2021
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Cegielski, Gustaw (author)Model order reduction (MOR) has been a field of active research in the past twenty years, more recently also in fluid dynamics. The main advantage of MOR is computational cost reduction, which, along with equally important accuracy, constitute main objective in the MOR community.<br/>A main ongoing issue is that data volumes in fluid flow...master thesis 2021
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Schouten, David (author)One of the preferred features of plastic is its high durability. This merit is its main disadvantage in the natural environment. When poorly disposed of, plastic waste can enter rivers from surface waters and subsequently end up in the ocean. Here, plastic spreads out over the entire ocean and ultimately ends in ocean gyres....master thesis 2021
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Kokee, Louis (author)Computational Fluid Dynamics based on RANS models remain the standard but suffer from high errors in complex flows. In particular, turbulent kinetic energy is over-produced in high strain rate regions, such as the near wake of wind turbine flows. Data-driven turbulence modelling methods aim to derive novel turbulence models with lower...master thesis 2021
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Levoni, Andrea (author)In the aviation, maritime and oil&gas sector, the potential benefit in yearly savings deriving from the reduction of turbulent skin-friction drag through active flow control are estimated in the millions of U.S. Dollars and million tonnes of CO2 emissions. Research in this topic has brought forward numerous techniques, offering enticing drag...master thesis 2021
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Lidtke, Artur K. (author), Klapwijk, M.D. (author), Lloyd, Thomas (author)Inflow turbulence is relevant for many engineering applications relating to noise generation, including aircraft wings, landing gears, and non-cavitating marine propellers. While modelling of this phenomenon is well-established for higher Mach number aerospace problems, lower Mach number applications, which include marine propellers, still...journal article 2021
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Zou, P. (author), Bricker, J.D. (author), Uijttewaal, W.S.J. (author)Concepts of a submerged floating tunnel (SFT) for novel sea-crossings have been researched in recent years. An SFT tube should be moored afloat by tensioned mooring systems to maintain the tube position under complex hydrodynamic loads. In-line force is amongst the dominant hydrodynamic parameters in the SFT cross-section design and the...journal article 2021
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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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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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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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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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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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Patil, Akshay (author)Rapid climate change and the corresponding estimated sea level rise can affect the performance of the coastal defense structures such as breakwaters, seawalls, and dikes. In order to improve these coastal defenses, a detailed understanding of the processes which contribute to wave run-up and overtopping over the coastal defenses needs to be...master thesis 2019