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Bogaerts, Charlie (author)
This study aims to quantify the aerodynamic behaviour of fixed pitch rotors with a diameter of 12.7 cm in axial descent, and its contribution to the attitude oscillations found for quadcopters under similar flight conditions. Wind tunnel tests are performed with an isolated rotor, as well as a complete quadcopter mounted inside a gimbal that...
master thesis 2023
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Hu, Willy (author)
Flying characteristics of a multi-engined light general aviation (GA) aircraft during and after an engine failure is often a major safety consideration when both designing and operating the aircraft. In the meantime, the propellers, being large rotating masses, can exert considerable gyroscopic effect on the aircraft during flight, itself...
master thesis 2023
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van Herwerden, Thijs (author)
Fiber reinforced composites have been increasingly used in the aerospace and automotive industry, due to their potential advantages for designing flexible, strong and lightweight structures. More recently they are also being considered for the manufacturing of marine propellers. Since they have the potential to lower the weight, lower the...
master thesis 2023
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Kooij, Robert (author)
From the desire to reduce the impact of traveling on the environment and the increase in fuel prices over the past years, the propeller has regained interest as a propulsion mechanism in the aviation industry. Two main reasons can be found in their high propulsive efficiency and ability to combine with electric motors. The scaling of the motors...
master thesis 2023
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de Gruijl, Wouter (author)
To make propellers more viable as a greener alternative to jet engines, the issue of propeller noise needs to be addressed. Previous propeller design optimization studies rarely take into account the effects on aerodynamic and aeroacoustic performance due to non-uniform inflow, the type of flow the propeller would experience if it was installed...
master thesis 2022
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Hendrix, Emile (author)
Ventilation events are the result of masses of air being transported from the water surface along the hull, through the propeller plane. Previous research in literature has shown that ventilation induces large and sudden variations of the load on the propeller. The response of the propulsion system had not been documented before. This is a...
master thesis 2020
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Nederlof, Robert (author)
Propellers have a high propulsive efficiency and can help in the reduction of fuel consumption of aircraft. For propellers which are mounted in front of the wing, the interaction of the slipstream with the lifting surfaces can alter the lift distribution significantly. In the use of modern optimization tools, fast and accurate analysis of the...
master thesis 2020
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van der Kroft, Koen (author)
Marine propulsion systems with diesel engines face continuous variations in propeller shaft speed and torque during operation, due to waves and changing rudder and water inflow angles. Traditional propulsion control systems do not take these variations into account, and attempt to maintain a constant shaft speed. These changing torques, in...
master thesis 2020
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van der Meer, Sylvain (author)
A propeller has a high propulsive efficiency, yet inherently leaves the air it propels swirling. The efficiency of a propeller can be enhanced by placing it in the tip vortex of a wing. Such a tip-mounted propeller configuration lets the vortex created by the wing and the vortex created by the propeller counteract each other, enhancing the...
master thesis 2020
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van der Leij, Maarten (author)
When propellers are operating near the free surface,  phenomenon called ventilation might occur. Due to insufficient immersion and high thrust loading, the propeller draws air, resulting in a reduced thrust. Reduced thrust may have consequences such as loss of propulsive power, control and steerability, and may therefore be...
master thesis 2019
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Liu, Xinyuan (author)
Increasing pressure of reducing fuel consumption has led to renewed interests in propeller propulsion devices for their high propulsive efficiency. In a propeller propulsion system, the torque applied to the propeller results in angular momentum in propeller slipstream. This angular momentum is not only a form of energy loss that does not...
master thesis 2018
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Kiakidis, Stamatis (author)
The emerging field of 3D printing has expanded to the fabrication of metallic components during the last decade. Among the most prominent applications is the production of aluminium bronze marine propellers by the Wire+Arc Additive Manufacturing (WAAM) method. This method incorporates a welding system attached to a robotic arm. The final product...
master thesis 2017
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Epema, Kitso (author)
Even though propellers are the oldest form of propulsion, they are still a popular choice for unmanned aerial vehicles (UAVs) and passenger aircraft in certain market segments. If the propellers are mounted on the wing, strong propeller-wing interactions alter the aerodynamic efficiency of the aircraft. Using low-order numerical models, it is...
master thesis 2017
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Huisman, T.J. (author)
The main objective of this Master’s thesis is to develop an optimization routine to improve ice-class propeller design methodology using the design space within the ice-class rules. Ice impacts on a ship propeller give additional design demands to ensure reliability and safety. Consequently, ice class propellers feature thicker blades, therewith...
master thesis 2015
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Channa, V.V. (author)
Open rotors are considered to have the potential to improve the fuel economy of aircraft significantly by improving the propulsive efficiency compared to the current generation turbofan engines. One of the possible configurations for the open rotors is the aft fuselage mounted contra-rotating pusher propeller. The aftfuselage mounted contra...
master thesis 2015
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Zhou, T. (author)
In some situations, concentrated vorticity which forms a vortical flow is involved in the inflow of a propeller. The impingement of the vortex on the propeller has several detrimental effects, e.g., foreign object damage during ground operation, impact on the propeller performance, unsteady loading on the blade, and tonal noise generation. The...
master thesis 2015
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Candade, A.A. (author)
Advanced propeller propulsion systems potentially provide a significant reduction in fuel burn compared to traditional turbofans. An alternative to the conventional aft-fuselage mounted pusher layout is the horizontal tailplane-tip mounted tractor propeller concept. The aim of this thesis is an experimental investigation of the aeroacoustic and...
master thesis 2015
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Stokkermans, T.C.A. (author)
In light of the energy crisis of the early 1970's, NASA and industry gained a renewed interest in high-speed propellers for improved propulsive efficiency and explored the idea of swirl recovery vanes (SRV) to generate a net thrust from the residual swirl in the propeller slipstream. After this first effort on the aerial application of SRV, only...
master thesis 2015
document
Janssen, R.F. (author)
The influence of laminar-turbulent transition on a propeller blade’s performance has been investigated in this study, both numerically and experimentally. The computational fluid dynamics (CFD) is performed using the TAU code developed by the German Aerospace Center, as well as an existing propeller lifting-line code. The laminar-turbulent...
master thesis 2015
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Hartuç, T. (author)
In this thesis both Wake Ingestion (WI) and Boundary Layer Ingestion (BLI) configurations have been investigated and analyzed with respect to their application to aircraft design. WI and BLI in the context used here means positioning the engine such that it ingests boundary layer fluid for the purpose of saving shaft-power. This research...
master thesis 2015
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