Searched for: collection%253Air
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Lovato, S. (author), Toxopeus, S.L. (author), Settels, J.W. (author), Keetels, G.H. (author), Kirichek, Alex (author)
The presence of mud layers on the bottom of ports and waterways can have negative effects on the hydrodynamic behaviour of marine vessels. This numerical study investigates the effect of muddy seabeds on the full-scale resistance of an oil tanker sailing straight ahead. The objective is to determine the influence of factors such as the...
journal article 2024
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Fu, Runnan (author), Pađen, I. (author), Garcia Sanchez, C. (author)
Due to lack of information and long geometry generation times, tree geometries are usually oversimplified or even ignored in Computational Fluid Dynamic (CFD) simulations that predict wind and pollutant dispersion in urban areas. Nevertheless, trees are known to impact local wind patterns and air quality levels. Thus, in this paper we explore...
journal article 2024
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Muscari, C. (author), Schito, Paolo (author), Viré, A.C. (author), Zasso, Alberto (author), van Wingerden, J.W. (author)
Actuator line modeling of wind turbines requires the definition of a free-stream velocity in a computational mesh and a regularization kernel to project the computed body forces onto the domain. Both choices strongly influence the results. In this work, a novel velocity sampling method—the so-called effective velocity model (EVM)—is...
journal article 2024
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Jonker, R. G. (author), AlYousif, A.Y. (author), Hofland, Bas (author), Antonini, A. (author), Zoon, Arthur (author), Smith, Gregory (author)
This study treats a detached homogenous low-crested structure (HLCS) made of Cubipod concrete elements placed seaward of a vertical wall (forming a basin in between) to reduce overtopping. Assessing the complex hydrodynamics and effects of changing the geometry of such a system in relation to overtopping reduction is challenging. The...
journal article 2024
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Ramaekers, M. J.F.G. (author), van der Vlugt, I.B. (author), Westenberg, J. J.M. (author), Perinajová, R. (author), Lamb, H. J. (author), Wildberger, J. E. (author), Kenjeres, S. (author), Schalla, S. (author)
Thoracic aortic aneurysm (TAA) is a local dilation of the thoracic aorta. Although universally used, aneurysm diameter alone is a poor predictor of major complications such as rupture. There is a need for better biomarkers for risk assessment that also reflect the aberrant flow patterns found in TAAs. Furthermore, hypertension is often...
journal article 2024
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Tosto, F. (author)
The vast majority of energy conversion systems currently makes use of fossil fuels, whose combustion generates harmful greenhouse gases. Transitioning to renewable energy sources is thus paramount to limiting the environmental impact of human activities on the climate. In this regard, the harvesting of wasted thermal energy constitutes a...
doctoral thesis 2023
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Lovato, S. (author)
The increasing size of today's ships is a major concern for navigation in confined waters. In order to ensure safe manoeuvres, port authorities prescribe, among others, a minimum under-keel clearance that must be maintained by the ships during navigation. However, the seabed of ports situated at the estuaries or along rivers is often covered by...
doctoral thesis 2023
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Perinajová, R. (author), van Ooij, Pim (author), Kenjeres, S. (author)
A long-time exposure to lack of oxygen (hypoxia) in some regions of the cerebrovascular system is believed to be one of the causes of cerebral neurological diseases. In the present study, we show how a combination of magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) can provide a noninvasive alternative for studying...
journal article 2023
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Başkaya, A.O. (author), Hickel, S. (author)
A conservative cut-cell immersed boundary (IB) method including gas-surface interactions (GSI) for the simulation of atmospheric entry flows under thermochemical nonequilibrium (TCNE) conditions is presented. The performance<br/>of the method is demonstrated for three test cases: a compression ramp, a cylinder, and a plasma wind tunnel ablator...
conference paper 2023
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Dutta, Debasish (author), Afzal, Mohammad Saud (author), Alhaddad, S.M.S. (author)
This study utilizes three-dimensional simulations to investigate scour in combined wave–current flows around rectangular piles with various aspect ratios. The simulation model solves the Reynolds-averaged Navier–Stokes (RANS) equations using the k–ω turbulence model, and couples the Exner equation to compute bed elevation changes. The model also...
journal article 2023
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Hobeika, N. (author), Garcia Sanchez, C. (author), Bluyssen, P.M. (author)
The corona pandemic accelerated a lot of studies about aerosol dispersion and different aerosol-generating tasks ranging in intensity from sneezing to breathing. Both measurements and numerical simulations were used to understand the behaviour of aerosols. For numerical simulations, Computational Fluid Dynamic (CFD) simulations were used;...
conference paper 2023
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Raghavan, V. (author), Simonetti, Irene (author), Lavidas, G. (author), Metrikine, A. (author), Cappietti, Lorenzo (author)
Utilization of Boundary Element Method (BEM) based on linear potential flow for modelling Oscillating Water Column (OWC) devices has gained popularity in the last two decades. The commercial BEM solver WAMIT has been used widely for modelling OWCs and validated using experimental modelling (Delauré et. al. 2003, Bingham et. al. 2015, Faÿ 2020)....
conference paper 2023
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Yildiz, B. (author), Uijttewaal, W.S.J. (author)
Compound weirs are used as flow diversion structures by adding additional flow resistance to the anticipated regions at the rivers. Furthermore, they are used for measuring and regulating flow rates accurately over a wide range of flow depths. When they are used for this purpose, the cross sections are generally selected as symmetrical having...
conference paper 2023
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Wang, J. (author), Yan, Xin ping (author), Boersma, B.J. (author), Lu, Ming jian (author), Liu, Xiaohua (author)
Printed circuit heat exchangers (PCHE) are designed to improve heat recovery and energy saving in supercritical CO<sub>2</sub> (S-CO<sub>2</sub>) power cycles. In the current study, a modified channel PCHE is proposed based on the regular straight channel and a zigzag channel. The thermal–hydraulic performance of four different types of PCHE...
journal article 2023
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Perinajová, R. (author), Álvarez-Cuevas, Concepción Borrás (author), Juffermans, Joe (author), Westenberg, Jos (author), Lamb, Hildo (author), Kenjeres, S. (author)
There is a pressing need to establish novel biomarkers to predict the progression of thoracic aortic aneurysm (TAA) dilatation. Aside from hemodynamics, the roles of oxygen (O<sub>2</sub>) and nitric oxide (NO) in TAA pathogenesis are potentially significant. As such, it is imperative to comprehend the relationship between aneurysm presence...
journal article 2023
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Holkema, K. J. (author), Aalbers, C. (author), Wellens, P.R. (author)
In head waves, water jet impacts due to run up can occur as a result of the structural configuration of some floating structures, reducing workability. Wave attenuation near the floater may reduce the risk of water jet impacts. This paper presents a numerical study of the performance and attenuation mechanisms of various plate type fixed free...
journal article 2023
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Puiman, L. (author), Almeida Benalcazar, E.F. (author), Picioreanu, C. (author), Noorman, H.J. (author), Haringa, C. (author)
In large-scale syngas fermentation, strong gradients in dissolved gas (CO, H<sub>2</sub>) concentrations are very likely to occur due to locally varying mass transfer and convection rates. Using Euler-Lagrangian CFD simulations, we analyzed these gradients in an industrial-scale external-loop gas-lift reactor (EL-GLR) for a wide range of...
journal article 2023
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Porcarelli, A. (author), Kruljević, B. (author), Langella, I. (author)
NO<sub>x</sub> formation in premixed, highly-strained, pure hydrogen-air flamelets is investigated at lean conditions. Detailed-chemistry, one-dimensional and two-dimensional simulations are performed on a reactants-to-products configuration with varying applied strain rate. The results highlight for the first time for lean pure-hydrogen...
journal article 2023
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Mauro, F. (author), Valentina, Enrico Della (author), Ferrari, Victor (author), Begovic, Ermina (author)
The increasing demand for offshore operations in deep water implies the necessity to predict station-keeping ability of offshore vessels since the early stages of design. To this end, besides developing sufficiently fast and accurate methodologies for the equilibrium resolution of the forces acting on the ship, it is of utmost importance to...
journal article 2023
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Zou, P. (author), Kim, Taeksang (author), Bricker, J.D. (author), Uijttewaal, W.S.J. (author)
The modelling of complex free surface flows is challenging due to the mobility and deformability of the interface and air entrainment characteristics, which are highly affected by turbulence. With the framework of Reynolds averaged Navier–Stokes (RANS) models and the volume of fluid (VOF) method, turbulence quantities at the air–water...
journal article 2023
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