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de Vries, S. (author), Verheijen, A.H. (author), Hoonhout, B.M. (author), Vos, S.E. (author), Cohn, Nicholas (author), Ruggiero, Peter (author)
This paper shows the first results of measured spatial variability of beach erosion due to aeolian processes during the recently conducted SEDEX2 field experiment at Long Beach, Washington, U.S.A.. Beach erosion and sedimentation were derived using series of detailed terrestrial LIDAR measurements of beach morphology during three low tide...
conference paper 2017
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Vos, S.E. (author), Lindenbergh, R.C. (author), de Vries, S. (author)
Sandy coasts are vulnerable to predicted climate change, but also need to safeguard coastal housing, recreation, safety and ecology. “Building with Nature” is an important approach for resilient coastal maintenance, but corresponding predictive modelling tools are partly inconclusive, due to a lack of measurements over multiple spatial and...
conference paper 2017
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de Vries, R. (author), Brown, M.T.H. (author), Vos, Roelof (author)
The potential benefits of hybrid-electric propulsion (HEP) have led to an increased interest in this topic over the past decade. One promising advantage of HEP is the distribution of power along the airframe, which enables synergistic configurations with improved aerodynamic and propulsive efficiency. The purpose of this paper is to present a...
conference paper 2018
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Lindenbergh, R.C. (author), Van Der Kleij, S. (author), Kuschnerus, M. (author), Vos, S.E. (author), de Vries, S. (author)
Sandy beaches are highly dynamic areas affected by different natural and anthropogenic effects. Large changes, caused by a storm for example, are in general well-understood and easy to measure. Most times, only small changes, at the centimeter scale, are occurring, but these changes accumulate significantly over periods from weeks to months....
journal article 2019
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Anders, K. (author), Lindenbergh, R.C. (author), Vos, S.E. (author), Mara, H. (author), de Vries, S. (author), Höfle, B. (author)
Geomorphic processes occur spatially variable and at varying magnitudes, frequencies and velocities, which poses a great challenge to current methods of topographic change analysis. For the quantification of surface change, permanent terrestrial laser scanning (TLS) can generate time series of 3D point clouds at high temporal and spatial...
journal article 2019
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Hoogreef, M.F.M. (author), Vos, Roelof (author), de Vries, R. (author), Veldhuis, L.L.M. (author)
This paper presents the results of a study into the effect of distributed hybrid-electric propulsion on aircraft performance and characteristics. To size these aircraft, a new preliminary sizing method for hybrid-electric aircraft with distributed propulsion, including aero-propulsive interaction, is combined with a modified Class-II weight...
conference paper 2019
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de Vries, R. (author), Hoogreef, M.F.M. (author), Vos, Roelof (author)
This study compares a hybrid-electric aircraft featuring a propulsive empennage and over-the- wing, distributed-propulsion to a conventional regional turboprop. The impact of multiple design parameters, mission requirements, and technology assumptions on maximum take-off mass and payload-range energy efficiency is evaluated, in order to...
conference paper 2019
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de Vries, R. (author), Brown, M.T.H. (author), Vos, Roelof (author)
The use of hybrid-electric propulsion (HEP) entails several potential benefits such as the distribution of power along the airframe, which enables synergistic configurations with improved aerodynamic and propulsive efficiency. This paper presents a comprehensive preliminary sizing method suitable for the conceptual design process of...
journal article 2019
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de Vries, R. (author), van Arnhem, N. (author), Avallone, F. (author), Ragni, D. (author), Vos, Roelof (author), Eitelberg, G. (author), Veldhuis, L.L.M. (author)
This experimental study focuses on the aerodynamic interaction effects that occur between an over-the-wing (OTW) propeller and a wing boundary-layer. An OTW propeller is positioned above the hinge-line of a wing featuring a plain flap. The measurements are carried out with and without axial pressure gradients by deflecting the flap and by...
conference paper 2019
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van Arnhem, N. (author), de Vries, R. (author), Vos, Roelof (author), Veldhuis, L.L.M. (author)
This paper presents an experimental and numerical study of the aerodynamic interaction between horizontal tail-mounted propellers and the airframe. A representative aircraft model was installed in a low-speed wind-tunnel and measurements were taken with an external balance to determine the effect of propeller installation on integral forces...
conference paper 2019
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Finger, D. Felix (author), de Vries, R. (author), Vos, Roelof (author), Braun, Carsten (author), Bil, Cees (author)
The number of case studies focusing on hybrid-electric aircraft is steadily increasing, since these configurations are thought to lead to lower operating costs and environmental impact than traditional aircraft. However, due to the lack of reference data of actual hybrid-electric aircraft, in most cases, the design tools and results are...
conference paper 2020
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Vos, S.E. (author), Spaans, Lennard (author), Reniers, A.J.H.M. (author), Holman, Rob (author), McCall, Robert (author), de Vries, S. (author)
Intertidal bars are naturally occurring morphological features along the waterline of sandy beaches. Present quantitative knowledge on intertidal bar behavior is limited, due to the scarcity of data resources and the limitations of traditional survey techniques. To investigate and quantify the cross-shore morphologic behavior of intertidal...
journal article 2020
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de Vries, R. (author), Hoogreef, M.F.M. (author), Vos, Roelof (author)
In this paper a design-of-experiments is performed with the objective of determining the improvements in aeropropulsive efficiency required for a reduction in the energy consumption of turboelectric transport aircraft, when compared to conventional, gas-turbine based alternatives. Simplified representations of the powertrain and the...
conference paper 2020
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Hoogreef, M.F.M. (author), de Vries, R. (author), Sinnige, T. (author), Vos, Roelof (author)
This paper presents a synthesis of aero-propulsive interaction studies performed at Delft University of Technology, applied to conceptual aircraft designs with distributed hybrid-electric propulsion (DHEP). The studied aero-propulsive interactions include tip-mounted propulsion, wing leading-edge distributed propulsion and boundary-layer...
conference paper 2020
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de Vries, R. (author), Hoogreef, M.F.M. (author), Vos, Roelof (author)
There has been a surge in research related to hybrid-/ electric propulsion (HEP) over the past decade, since this technology has the potential to reduce the energy consumption and in-flight emissions of commercial aircraft and, therefore, to bring the aviation sector closer to the sustainability targets established by the European Commission [1]...
journal article 2020
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van Arnhem, N. (author), de Vries, R. (author), Sinnige, T. (author), Vos, Roelof (author), Eitelberg, G. (author), Veldhuis, L.L.M. (author)
Advances in aerodynamic and propulsive efficiency of future aircraft can be achieved by strategic installation of propellers near the airframe. This paper presents a robust and computationally efficient engineering method to estimate the load distribution of a propeller operating in arbitrary nonuniform flow that is induced by the airframe...
journal article 2020
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van Arnhem, N. (author), de Vries, R. (author), Sinnige, T. (author), Vos, Roelof (author), Veldhuis, L.L.M. (author)
In this combined experimental and numerical study, the propeller–airframe aerodynamic interaction is characterized for an aircraft configuration with propellers mounted to the horizontal tailplane. The contributions of the propeller and airframe to the overall loading are distinguished in the experimental analyses by using a combination of...
journal article 2021
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de Vries, R. (author), van Arnhem, N. (author), Avallone, F. (author), Ragni, D. (author), Vos, Roelof (author), Eitelberg, G. (author), Veldhuis, L.L.M. (author)
This experimental study focuses on the aerodynamic interaction between an over-the-wing (OTW) propeller and a wing boundary layer. An OTW propeller is positioned above the hinge line of a wing with a trailing-edge flap. Measurements are carried out with and without axial pressure gradients by deflecting the flap and by extending the flat upper...
journal article 2021
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de Vries, R. (author), van Arnhem, N. (author), Sinnige, T. (author), Vos, Roelof (author), Veldhuis, L.L.M. (author)
This article describes an experimental investigation of the aerodynamic interaction that occurs between distributed propellers in forward flight. To this end, three propellers were installed in close proximity in a wind tunnel, and the changes in their performance, flow-field characteristics, and noise production were quantified using...
journal article 2021
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Vos, S.E. (author), van IJzendoorn, Christa (author), Kuschnerus, M. (author), de Vries, S. (author)
The European beach-dune systems are under increasing pressure due to urbanization, beach tourism and the effects of climate change like rising sea level and increased storm intensity. Building with nature solutions (Stive et al., 2013) are advocated as an effective and adaptable approach to protect sandy coasts in the future. This approach...
conference paper 2022
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