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Barker, Evan (author)
As market growth projections for Urban Air Mobility vehicles (UAMs) skyrocket, their presence in urban environments is likely to become increasingly prevalent, as will their noise. This creates a disturbance to both humans and wildlife, previously unaffected by aircraft noise. Further reinforcing the concern is the new multi-rotor designs, which...
master thesis 2023
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Pockelé, Josephine (author)
Wind turbine noise is one of the grand challenges in the public acceptance of onshore wind farm projects. The field of psychoacoustics identifies the auralisation of wind turbine noise as a link between technical design and annoyance estimation. There is currently limited work on the auralisation of wind turbine noise, and none targets an...
master thesis 2023
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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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RAGHAVARAJU, JAHNAVI (author)
Wind tunnel investigations of cycling aerodynamics are conducted in air streams that are designed to have minimum turbulence. This is not representative of the true, turbulent wind environment encountered by a track cyclist in an indoor velodrome. The goal of this thesis, broadly speaking, is to assess the effects of this turbulence on cycling...
master thesis 2023
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Perez, Paul (author)
Desert sand acoustic emissions are produced when a “sonic sand” is sheared locally or by a natural dune slipface avalanche, resulting in a brassy sound between 50 and 400 Hz. This type of sediment exhibits particular granulometric, shape and surface characteristics, due to the grains’ erosion and transport history, and emits sounds when the...
master thesis 2023
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Jose, Nikhil (author)
Surfaces that induce slip at the wall have been shown to reduce skin friction drag in the turbulent regime. While superhydrophobic and liquid-infused surfaces are capable of drag reduction in turbulent hydrodynamic flows, neither would be feasible in aerodynamic applications due to the added roughness and the minuscule slip lengths created by...
master thesis 2023
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Moriaux, Olivier (author)
Unsteady surface pressures shed light on the turbulent structures of boundary layer flow, which dictate for a large part the aerodynamic and aeroacoustic performance of aerodynamic bodies submersed in a flow. Remote microphone probes (RMP), e.g., pinhole probes, provide advantages compared to flush-mounted probes because of their reduced sensing...
master thesis 2023
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Van Dam, Stijn (author)
With new rovers landing on Mars, like the Perseverance rover in 2020, the interest in Mars has grown recent years. The atmospheric conditions on Mars result in challenging conditions due to its low density atmosphere and extremely low temperatures. With a density on Mars that is 1% of that on Earth, creating sufficient lift for vehicles to fly...
master thesis 2022
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Carrasco Grau, Julio (author)
In the last decades, the prevailing belief that smooth surfaces offer the lowest drag has been challenged often. Scholars have, for example, introduced rough and modified surfaces to reduce turbulent skin friction. One of the technologies proposed in the literature is an array of chevron-shaped protrusions; however, there is no academic...
master thesis 2022
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Koutsoukos, Alexandros (author)
The Advisory Council of Aviation Research has set the future goals of sustainable development in aviation by reducing pollutant emissions of CO2 by 75% and 90% in NOx emissions per passenger kilometre and noise emission by 65% of the perceived noise level compared with the measurements in 2000. This demand has led to the development of new...
master thesis 2022
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de Haan, Wouter (author)
Due to the rising demand for short-range air travel and the desire for aircraft driven by electric propulsion, there has been a renewed interest in propeller research. Despite the high potential aerodynamic efficiency of propellers, their excessive noise emissions prevent a widespread use on aircraft. A gradient based optimization study is...
master thesis 2021
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Kalk, Peer (author), Zevenbergen, Constantijn (author)
As electric vehicles are quickly taking over the automotive industry, electric airplanes are also starting their upswing. With air travel and transport in general being a large polluter of CO2 gases, the transition to electric flight becomes more prominent every year. This transition is starting small with non-commercial airplanes. Several...
bachelor thesis 2021
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Pandey, Akash Pandey (author)
Advancements in technology have made commercial unmanned aerial vehicles reliable and readily available, leading to an exponential rise in their market demand over the past few years. COVID-19 has further accelerated this growth through an increase in demand for contact-less delivery and crowd monitoring systems. However,...
master thesis 2021
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Tseremoglou, I. (author)
Cargo airlines' Revenue Management (RM) departments oversee the acceptance/rejection process of incoming bookings. The overarching goal is to accept as many bookings as possible, hence maximizing profit, while avoiding overbooking and offloading of already accepted shipments, to ensure customer satisfaction. This whole process is characterized...
master thesis 2020
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van Hove, Alouette (author)
Accurate measurement of emissions (i.e. volume flow rate multiplied by concentration) is vital to the control and reduction of air pollution. We quantify the uncertainty of flow measurements by S-type pitot tubes in narrow exhaust stacks (diameter < 0.5 m) in support of recent European Union (EU) regulations for emissions from medium-size...
master thesis 2018
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Hemmen, Patrick (author)
Hybrid laminar flow control (HLFC) reduces skin friction drag, by combining boundary layer suction with pressure gradient tailoring to delay boundary layer transition. This research addresses two key developments required to perform the aerodynamic design of suction-type HLFC components. First, an existing numerical transition prediction tool...
master thesis 2018
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Meijs, Lars (author)
Where a relatively small part (less than 1%) by volume of world trade is represented by air transport, the orientation towards high value products results in a share of almost 35% of international trade in value. But where data of the amount of trade between countries is highly available, the actual routing of those traded goods is not known at...
master thesis 2017
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van Mourik Broekman, Jeremy (author)
The high efficiency of open rotor propulsion has led to a comeback of propeller propulsion systems in recent years. The main issue preventing wide application of the technology is its high noise level. One of the main contributors to this noise is the pressure fluctuations generated during the interaction between a propeller tip vortex and a...
master thesis 2017
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Vimanyu Kumar, Vimanyu (author)
The growing importance of renewable energy to meet the demands of growing population has driven much focus for research in the wind energy sector. Currently most of the power production in the wind energy sector is done using the Horizontal Axis Wind Turbine (HAWT). due to its higher efficiency and reliability as compared to Vertical Axis Wind...
master thesis 2017
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Dijkstra, Pieter (author)
The thesis is focused on designing a tip-region airfoil for a multi-MW wind turbine. It is approached with the objective of optimizing the geometry of the airfoil for the best trade-off between aero-acoustics and aerodynamic requirements. Using the wind turbine noise prediction tool SILANT it is established that trailing edge noise is the most...
master thesis 2015
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