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document
Hemelaar, Senne (author)
While the assumption of incompressible flow has been the prevailing standard for numerical simulations of wind turbine aerodynamics, the limit of this assumption is approached as the industry progresses towards increasingly higher operational tip speeds. This thesis explores the implications of compressibility and transonic flow phenomena,...
master thesis 2024
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Popi, George (author)
Nuclear power is increasingly seen as a potential solution to the decarbonization of the energy sector in the coming decades. However, one of the main causes of downtime for current-generation nuclear reactors is the phenomenon of Grid-To-Rod-Fretting (GTRF) inside the reactor core. This is predominantly caused by Fluid-Structure Interaction ...
master thesis 2024
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Plijter, Jurrien (author)
This thesis investigates the aerodynamics of a propeller-wing-flap system, spurred by the growing interest in propeller-driven aircraft and the potential introduction of distributed electric propulsion. The research focuses on the complex flowfield involving the interaction of the propeller slipstream with the main wing and flap at high-lift...
master thesis 2023
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Melissaris, Themistoklis (author), Schenke, S. (author), Bulten, Norbert (author), van Terwisga, T.J.C. (author)
Propeller cavitation erosion prediction at an early design stage is becoming more and more important since it is one of the key constraints in the search for maximum propeller efficiency. Despite the experience from model tests, cavitation erosion research on actual ship scale is very limited. In this study, an attempt is made to assess the...
journal article 2022
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Hadžiabdić, Muhamed (author), Hafizović, Mahir (author), Ničeno, Bojan (author), Hanjalic, K. (author)
We report on the application and comparative assessment of two rational turbulence modelling approaches for the computer simulation of air flow and pollutant dispersion in real urban environment: a stand-alone unsteady Reynolds-averaged Navier-Stokes eddy-viscosity model (URANS), and its blend with Large-eddy simulations (LES) in a hybrid...
journal article 2022
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Hussain, Mohammed Muaaz (author)
The advent of global warming has brought an increased interest in non-conventional sources of energy, one of which is nuclear energy. Threatening the almost year-round functioning of nuclear power plants are Flow-Induced Vibrations (FIV). One such mechanism, Vortex-Induced Vibration (VIV), holds importance in areas of cross flow in nuclear power...
master thesis 2021
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Melissaris, Themistoklis (author), Schenke, S. (author), Bulten, Norbert (author), van Terwisga, T.J.C. (author)
Predicting the cavitation impact loads on a propeller surface using numerical tools is becoming essential, as the demand for more efficient designs, stretched to the limit, is increasing. One of the possible design limits is governed by cavitation erosion. The accuracy of estimating such loads, using a URANS approach, has been investigated....
journal article 2020
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Derksen, Adriaan (author)
Recent innovations in the off-shore wind industry have lead to bigger wind turbines and taller support structures. These towers can suffer from vortex-induced vibrations (VIV). The present work couples the open-source CFD solver OpenFOAM with a structural solver to investigate these fluid-structure interactions (FSI) effects in more detail. 2D...
master thesis 2019
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Abbasi, A. (author), Annor, F.O. (author), van de Giesen, N.C. (author)
A 3-D numerical method is developed to investigate the spatial distribution of surface fluxes over heterogeneous surfaces in (semi-)arid regions. Quantifying the effects of changes in the momentum, thermal and moisture roughness lengths on the airflow and fluxes in the ABL is important for water resources management and local climate studies....
journal article 2018
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Steijger, Miranti (author)
master thesis 2017
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Kottapalli, S. (author)
Flow induced vibrations (FIV) is a known problem in nuclear reactors. The interaction between the turbulent flow of the coolants and the fuel rod bundles generates vibrations which are undesirable. These vibrations can be a major cause of fatigue failures, stress corrosion cracking and fretting wear of materials, which lead to stand-still costs....
master thesis 2016
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Nanda, S. (author)
The ERCOFTAC test case for flow past a square-prism at a Reynolds number of 21,400 was studied numerically using the flow solver ReFRESCO. The main objectives were to evaluate the performance of a Reynolds Averaged Navier-Stokes (RANS) based turbulence models in Unsteady RANS (URANS) simulations, identify sensitivities to numerical parameters...
master thesis 2016
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Dingemans, N.T. (author)
Moonpools are vertical wells used on most offshore vessels at Huisman Equipment. The oscillations in the moonpool lead to a significant increase in resistance for vessels in transit conditions. In the concept design phase it has proven difficult to predict the moonpool behaviour, as well as the effect of implementing appendages within a long...
master thesis 2016
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Palkin, Egor V. (author), Mullyadzhanov, Rustam I. (author), Hadziabdic, M (author), Hanjalic, K. (author)
Relevance. Characteristics of separated turbulent streams are of great importance when designing effective hydroand thermal power plants equipment. In such streams the flow regimes with harmful quasi-periodic high-amplitude oscillations of velocity and pressure behind the body are implemented. Thus, the knowledge on the ways of controlling...
journal article 2016
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Gurunath, S. (author)
In order to ramp up the conversion ratios and burn-up of nuclear reactors, it is inevitable to go to tightly packed fuel rods in the reactor. These nuclear reactors with tightly packed rod-bundles are characterized by interesting flow patterns, different from the ones encountered in regular channel and pipe flows. The correct prediction and...
master thesis 2012
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Sterenborg, J.J.H.M. (author), Van Zuijlen, A.H. (author), Bijl, H. (author)
In order to validate fluid-structure interaction solvers, a one degree of freedom (1 DOF) aeroelastic experiment is performed. A rigid wing with an harmonically actuated flap, is suspended by springs to allow a free heaving motion. Displacements and time dependent aerodynamic forces are measured for reduced flap frequencies ranging from k = 0.1...
conference paper 2011
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Braza, M. (author), El Akoury, R. (author), Martinat, G. (author), Hoarau, Y. (author), Harran, G. (author), Chassaing, P. (author)
This paper analyses the performances of adapted URANS and DES turbulence^modelling for high-Reynolds 2D and 3D aerodynamic flows with a pronounced periodic character. The flow configurations is the NACA0012 airfoil in pitch (experimental test-case by Mc Croskey & Mc Alistair, 1976) at Reynolds number 0.98x10^6, as well as the inherently unsteady...
conference paper 2006
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Davidson, L. (author)
The SAS model (Scale Adapted Simulation) was invented by Menter and co-workers. The idea behind the SST-SAS k-omega model is to add an additional production term -- the SAS term -- in the omega equation, which is sensitive to resolved (i.e. unsteady) fluctuations. When the flow equations resolve turbulence, the length scale based on velocity...
conference paper 2006
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Panara, D. (author), Porta, M. (author), Schoenfeld, T. (author)
The use of wall functions has been investigated for LES and URANS numerical simulation in pulsating and oscillating channel flow applications. The results show that the wall function approach is accurate in the so-called quasi-steady regime but there are discrepancies with the experimental results in the intermediate frequency range. A special...
conference paper 2006
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