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Oude Nijhuis, A.C.P. (author)
Scanning radars are promising sensors for atmospheric remote sensing, giving potential to retrieve parameters that characterize the local air dynamics during rain. For the observation of air motion, radars are relying on the backscatter of particles, which can, for example, be raindrops or insects. To measure wind vectors and turbulence...
doctoral thesis 2019
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van Hout, R.L.H. (author), Eisma, H.E. (author), Elsinga, G.E. (author), Westerweel, J. (author)
In many applications, finite-sized particles are immersed in a turbulent boundary layer (TBL) and it is of interest to study wall effects on the instantaneous shedding of turbulence structures and associated mean velocity and Reynolds stress distributions. Here, 3D flow field dynamics in the wake of a prototypical, small sphere (D+=50, 692&lt...
journal article 2018
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Mobertz, Xander (author)
Implementation of touchscreen technology on the flight deck has already been announced by multiple aircraft manufacturers. However, a number of unsolved challenges still stand in the way of large scale implementation. One of these challenges comes from using touchscreens as input device in a highly dynamic and turbulent environment. Effects from...
master thesis 2017
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Akkermans, Christ (author)
The influence of using different chemistry model and different chemical kinetics schemes on modeling combustion inside a rocket engine igniter are investigated. An igniter for a LOX/CH4 rocket engine is designed and a CFD model is developed which is used to model the designed igniter. Verification and validation methods are discussed.<br/><br/>...
master thesis 2017
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Schoenmaker, Lars (author)
In this thesis diffuser performance will be simulated with computational fluid dynamics, which will be done with the program Ansys Fluent. The expanding geometry creates an adverse pressure gradient and under certain conditions there will also be separation.<br/><br/>At first a relative simple simulation will be done of a one-directional...
master thesis 2017
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Schulte, Ruben (author)
Nocturnal weather can have significant impact on society. Dangerous conditions can occur after clear sky nights with weak winds. The lack of turbulent mixing during these nights can cause the near-surface temperature to rapidly decrease. A single short-lived turbulent event can renew turbulent mixing and hamper/stop the formation of fog or...
master thesis 2017
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Bos, R. (author)
Wind turbines are the largest rotating machines on the planet, operating in some of the most remote and hostile areas. During a lifespan of several decades, they have to withstand storms, waves, and gusts (and preferably produce electricity in the process). Yet, designers cannot make them too strong. Every additional kilogram of mass has to be...
doctoral thesis 2017
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van Emmerik, T.H.M. (author), Steele-Dunne, S.C. (author), Hut, R.W. (author), Gentine, Pierre (author), Guerin, MF (author), Oliveira, Rafael (author), Wagner, Jim (author), Selker, John (author), van de Giesen, N.C. (author)
Trees play a crucial role in the water, carbon and nitrogen cycle on local, regional and global scales. Understanding the exchange of momentum, heat, water, and CO 2 between trees and the atmosphere is important to assess the impact of drought, deforestation and climate change. Unfortunately, ground measurements of tree properties such as mass...
journal article 2017
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van den Engel, P.J.W. (author), Kurvers, S.R. (author)
An overview is given of recent developments in the use of a system of inducing natural air supply via the façade in the Netherlands. This is followed by a review of the results of measurements from climate chamber experiments of its inducing ventilation performance and detailed insights gained from related experiments of climate chamber...
journal article 2017
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Smyrnis, A. (author)
Block mattresses or block mats are, nowadays, very commonly applied as protection in a large range of applications either against flow or wave loads. Specifically, this large range of applications contains offshore pipeline protection and stabilization, erosion and scour protection, protection of embankments and river banks (slope protection)....
master thesis 2017
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Fiscaletti, D. (author)
The present work is an experimental and numerical investigation of the small-scale motions in turbulent free-shear flows. In the far-field turbulence of a jet at high Reynolds number (Re? = 350) hot-wire anemometry (HWA) is applied to measure time series of flow velocity. By filtering these time series, large- and small-scale velocity...
doctoral thesis 2016
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van Beinum, A.S. (author), Farah, H. (author), Wegman, F.C.M. (author), Hoogendoorn, S.P. (author)
Turbulence in traffic is a commonly known phenomenon, but the exact characteristics of this phenomenon are not yet clear. It reflects individual changes in speed, headways, and lanes in the traffic stream. The currently used freeway design guidelines prescribe different measures for handling turbulence, such as sufficient ramp spacing, and...
conference paper 2016
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Spectral transfer processes in magnetohydrodynamic (MHD) turbulence are investigated by decomposition of the velocity and magnetic fields in Fourier space into helical modes. In 1992, Waleffe (Phys. Fluids A, 4:350 (1992)) used this decomposition to calculate triad interactions for isotropic hydrodynamic turbulence and determined whether a given...
conference paper 2015
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Van der Dussen, J.J. (author)
Clouds have a strong net cooling effect on our planet, as they reflect a large part of the incident solar radiation. To be able to make accurate forecasts of the global climate, cloudiness should therefore be correctly represented by climate models. Currently, however there are large differences in the forecasted temperature increase among...
doctoral thesis 2015
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Radermacher, M. (author), De Wit, L. (author), Uijttewaal, W.S.J. (author), Winterwerp, J.C. (author)
When dredging in sensitive environments, efforts have to be made to limit the free dispersal of suspended fine sediment from the dredging spill. Especially the use of hanging silt curtains as an environmental mitigation measure is widespread. Despite frequent application, their ability to reduce turbidity levels through vertical diversion of...
journal article 2015
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Tomas, J.M. (author), Pourquie, M.J.B.M. (author), Jonker, H.J.J. (author)
Predicting pollutant dispersion in urban environments requires accurate treatment of obstacle geometry, inflow turbulence and temperature differences. This paper considers both the influence of thermal stratification and the presence of a single obstacle on pollutant dispersion in turbulent boundary layers (TBLs). Turbulent flow over a fence...
journal article 2015
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Pavlioglou, S. (author)
The rudder-propeller, as the azimuthing thruster was originally called, can be rotated 360 degrees and is capable of delivering full propulsive power in any direction. The azimuthing thruster makes use of a mechanical transmission in order to deliver the power from the prime mover to the propeller. The good maneuverability and the absence of a...
master thesis 2015
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Boersma, B.J. (author), Pecnik, R. (author), Nemati, H. (author), Peeters, J.W.R. (author)
In this paper we discuss the effect of sharp property variations on the turbulent heat transfer in fluids close the critical point. The governing equations for this flow regime are discussed, a short description of the numerical tools that have been developed to study these flows is given. Finally, some results for supercritical heat transfer in...
journal article 2015
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Hovenga, M.J. (author)
Turbulence distances are a major design criteria in the design of new freeways and the modifications of freeways. In the Dutch freeway design guideline (NOA) turbulence distances are applied to determine the minimal distance between on-ramps and off-ramps to enter and exit the freeway, or to switch from the one freeway to the other, and lane...
master thesis 2014
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Tokgöz, S. (author)
Taylor-Couette flow is defined as the flow confined between two coaxial cylinders which can rotate independently. Several different flow states can be observed in the gap between the cylinders by changing the rotation speeds and the rotating directions of the cylinders. The aim of this thesis is to investigate the previously reported change of...
doctoral thesis 2014
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