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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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Sousa da Costa, Tiago (author)
Micro-propulsion technology is under rapid development and considerably extends the mission capabilities of small spacecraft. However, the flow in conventional nozzles on a microscale is relatively viscous, which, combined with the bounding nozzle walls, leads to low efficiencies. Aerospike nozzles, on the other hand, offer...
master thesis 2021
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Meijer, Ralf (author)
The lifespan of internal reforming solid oxide fuel cells (SOFCs) is not yet sufficient. Among other design challenges, this is due to detrimental carbon deposition formations. This must be mitigated, without compromising the power output and efficiency of the fuel cell for it to become a commercial viable product. The carbon that is deposited...
master thesis 2021
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Zaky, Michael (author)
Gas turbines for power generation use lean premixed flames to adhere to the strict pollutant emissions regulations. Unfortunately, this often leads to thermoacoustic instabilities. These instabilities can lead to failure of system components, flame blow-off or flashback and a reduction in efficiency. Especially the high frequency transverse...
master thesis 2021
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Haafkes, Thom (author)
During berthing operations of ships, the horizontal thrusters cause a hydraulic load on the quay wall and bed. This could eventually lead to scour holes in the bed, which may affect the structural integrity of the quay wall. This thesis is about a numerical simulation of a bowthruster jet which is deflected by a quay wall and the focus of this...
master thesis 2021
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Chaves García-Mascaraque, Adrián (author)
A formulation based on the evaluation of power conversions within the system allows to overcome the limitations of conventional momentum analyses to study tightly coupled airframe-propulsion configurations such as Boundary Layer Ingestion. The so-called power balance method is applied in a CFD framework to gain insight about the application of...
master thesis 2021
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Leijs, Karin (author)
Reducing dredging activities in the harbors brings benefits both economically and environmentally. However, this means that ships may have to sail very close to or even through the mud layer on the seabed, with possible effects on ships’ resistance and manoeuvrability. This study has made a step in understanding these effects on ships’...
master thesis 2021
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Bockstael, Marnix (author)
Marine structures can sustain damage due to violent wave impacts that are characterized by complex dynamics involving both water and air. Methods that predict impacts loads for structural design often assume the water as incompressible. These predictions can be inaccurate during impacts where air is entrained in water, as that greatly increases...
master thesis 2021
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Bosma, Lars (author)
Throughout the last century, high energy-density fossil fuels have been the main energy source for merchant shipping. As the world tries to minimize the effects of global warming, shipowners are forced to significantly reduce their $CO_2$ emissions. Because alternative fuels are expensive, the interest in wind energy, which has been the single...
master thesis 2021
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Aarts, Aukje (author)
During the last decades, the development of high-rise increased quickly. The Eurocode is frequently used to make wind calculations for high-rise structures. To make those calculations, the dynamic wind load is simplified to a conservative equivalent static load. An alternative to calculate wind loads is a physical wind tunnel test. Wind tunnel...
master thesis 2021
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Alberts, Jasper (author)
A wall-resolved Large Eddy Simulation (LES) of a wing-body junction is performed. The aim is to generate high-fidelity junction flow data to be used in a data-driven turbulence modelling approach, specifically to improve the accuracy of RANS-simulations in junction flows. The simulation is performed on a 61.5 million C-grid body fitted mesh in...
master thesis 2021
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Kaiser, Philipp (author)
The increasing importance of climate change and stricter regulations for greenhouse gas emissions raise the pressure on the automotive industry to develop more efficient products. Besides a reduction of emissions by new combustion engines, electric vehicles are being introduced to lower the fleet fuel economy. Especially this new drivetrain...
master thesis 2021
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Nelissen, M.M. (author)
In the future, fossil fuels will be replaced by renewable sources. Hydrogen seems to be a promising energy carrier (fuel). A lot of research has been conducted on the combustion of hydrogen, but the effect of the high diffusivity of hydrogen compared to other species (differential diffusion) was often not included in simulations of turbulent...
master thesis 2021
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Johri, Kartikay (author)
There is a requirement for localised efficient electricity generation systems that increase the efficiency of power plants and reduce wasted heat from other engineering applications such as cement manufacturing units and brick kilns. Organic Rankine Cycle (ORC) power systems use organic fluids and low-grade heat sources to accomplish this. Lack...
master thesis 2020
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Desypris, Georgios (author)
Flameless combustion, or MILD combustion is a technology that enables stable combustion with high efficiency while maintaining very low NOx and soot emissions. It is characterized by uniform heat flux and can be achieved when fuel and preheated oxidant jets are mixed into a strong recirculating flow. It is a complex process which combines...
master thesis 2020
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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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Quan Reyes, Diego (author)
The current economic-development system based on fossil fuels can no longer sustain itself and is incapable of satisfying the needs of the global population. Nearly one third are unable to meet even their most basic needs that involve harnessing energy for everyday essential tasks such as maintaining livable shelter and food preparation. Models...
master thesis 2020
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Mukhopadhyay, S.K. (author)
Although significant strides have been made with regards to increasing the fuel economy of commercial passenger aircraft, the reduction of the environmental footprint remains of the utmost importance. The flow development over an aero-engine spinner will affect the velocity distribution over the fan of the engine and this affects the estimation...
master thesis 2020
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Koolstra, Rense (author)
Porous media are used for a wide variation of applications in energy production and storage. One of those applications is the storage of heat which are of great importance in the renewable energy transition. Most literature reported limit itself only to one single thermal conductivity for the porous media. In reality however, the porous media...
master thesis 2020
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Khurana, Siddhant (author)
Over the past decades, numerous methods have been used to study acoustic liners through their impedance, of which numerical methods are of particular interest. Despite their advantages, numerical methods are bounded by certain drawbacks. One such drawback stems from the need to accurately discretize the liner geometry, which can lead to large...
master thesis 2020
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