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Wei, P. (author), Uijttewaal, W.S.J. (author), Spanjers, H. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)
Gas-mixing is commonly applied in anaerobic digesters, yet the resulting flow and hydraulic mixing are difficult to evaluate because of limited full-scale experimental data and uncertainties in integrating sludge rheological data. This study used computational fluid dynamics (CFD) to assess the impact of treated sludge rheology on flow and...
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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Hosseini, A. (author), Dhiman, Vinod (author), Meijer, Koen (author), Zeilstra, Christiaan (author), Hage, Johannes (author), Peeters, Tim (author), Offerman, S.E. (author), Yang, Y. (author)
A three-dimensional computational fluid dynamics (CFD) model for the HIsarna off-gas system is set up and validated by real plant data. In the model detailed reaction mechanism and kinetic data for post-combustion of CO-H2 mixture and carbon particles are incorporated. The results are presented and discussed in another study (Part 1) by the...
journal article 2022
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Haringa, C. (author), Tang, W. (author), Noorman, H.J. (author)
The compartment model (CM) is a well-known approach for computationally affordable, spatially resolved hydrodynamic modeling of unit operations. Recent implementations use flow profiles based on Computational Fluid Dynamics (CFD) simulations, and several authors included microbial kinetics to simulate gradients in bioreactors. However, these...
journal article 2022
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Lovato, S. (author), Kirichek, Alex (author), Toxopeus, S.L. (author), Settels, J.W. (author), Keetels, G.H. (author)
When investigating the effect of muddy seabeds on marine vessels using Computational Fluid Dynamics (CFD) software, one challenge is to adequately describe the complex non-Newtonian fluid behaviour of mud. Although a number of rheological models have been proposed in the past, mud sediments are often simply regarded either as highly viscous...
journal article 2022
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Hur, C. (author), Ferreira, Carlos (author), Schepers, Gerard (author)
Horizontal axis wind turbines (HAWTs) experience yaw misalignments due to the physical limitations of yaw controllers and various novel active yaw controls. Moreover, the motion of floating offshore wind turbines (FOWTs) accelerates yaw misalignment. The blade element momentum (BEM) method is widely used due to its computational efficiency for...
journal article 2022
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Rijkens, A.A.K. (author), Mikelic, A. (author)
The seakeeping behaviour of naval ships is an important factor for its operational effectiveness, as vessels with good seakeeping abilities are able to go to sea and successfully execute their missions despite possible adverse weather conditions. Hence, it is not surprising that the hydrodynamic assessment of a new frigate type hull forms is...
journal article 2022
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Hogervorst, T.A. (author), Nane, R. (author), Marchiori, Giacomo (author), Qiu, Tong Dong (author), Blatt, Markus (author), Rustad, Alf Birger (author)
Scientific computing is at the core of many High-Performance Computing applications, including computational flow dynamics. Because of the utmost importance to simulate increasingly larger computational models, hardware acceleration is receiving increased attention due to its potential to maximize the performance of scientific computing....
journal article 2022
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Lovato, S. (author), Keetels, G.H. (author), Toxopeus, S. L. (author), Settels, J. W. (author)
This article presents a new turbulence closure based on the k-ω SST model for predicting turbulent flows of Herschel–Bulkley fluids, including Bingham and power-law fluids. The model has been calibrated with direct numerical simulations (DNS) data for fully-developed pipe flow of shear-thinning and viscoplastic fluids. The new model shows...
journal article 2022
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Zou, P. (author), Bricker, J.D. (author), Chen, L. Z. (author), Uijttewaal, W.S.J. (author), Ferreira, Carlos (author)
In order to assess the dynamic performance of a submerged floating tunnel (SFT) subject to flow-induced vibration (FIV) conditions in a practical engineering application, a one-way fluid–structure interaction (FSI) model consisting of multi-scale hydrodynamic solvers combined with the finite element method (FEM) is established. A typical long...
journal article 2022
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Steiner, J. (author), Dwight, R.P. (author), Viré, A.C. (author)
The state-of-the-art in wind-farm flow-physics modeling is Large Eddy Simulation (LES) which makes accurate predictions of most relevant physics, but requires extensive computational resources. The next-fidelity model types are Reynolds-Averaged Navier–Stokes (RANS) which are two orders of magnitude cheaper, but resolve only mean quantities...
journal article 2022
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Tsekos, C. (author), de Voogt, D. (author), de Jong, W. (author), Padding, J.T. (author)
This work focuses on the numerical modelling and experimental validation of the hydrodynamic behaviour of a novel 50 kW<sub>th</sub> indirectly heated bubbling fluidized bed steam reformer. The hydrodynamic behaviour of fluidized beds with immersed vertical tubes and complex fluidized bed geometries in general have not been thoroughly...
journal article 2022
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Wang, Lu (author), Robertson, Amy (author), Jonkman, Jason (author), Kim, Jang (author), Shen, Zhi‐Rong (author), Koop, Arjen (author), Chandramouli, P. (author), Viré, A.C. (author), Ramesh Reddy, L. (author)
Currently, the design of floating offshore wind systems is primarily based on mid-fidelity models with empirical drag forces. The tuning of the model coefficients requires data from either experiments or high-fidelity simulations. As part of the OC6 (Offshore Code Comparison Collaboration, Continued, with Correlation, and unCertainty (OC6) is a...
journal article 2022
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Lovato, S. (author), Toxopeus, S.L. (author), Settels, J.W. (author), Keetels, G.H. (author)
The ship’s resistance and manoeuvrability in shallow waters can be adversely influenced by the presence of fluid mud layers on the seabed of ports and waterways. Fluid mud exhibits a complex non-Newtonian rheology that is often described using the Herschel–Bulkley model. The latter has been recently implemented in a maritime finite-volume CFD...
journal article 2022
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Haringa, C. (author)
Euler-Lagrange CFD simulations, where the biotic phase is represented by computational particles (parcels), provide information on environmental gradients inside bioreactors from the microbial perspective. Such information is highly relevant for reactor scale-down and process optimization. One of the major challenges is the computational...
journal article 2022
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Puiman, L. (author), Abrahamson, Britt (author), van der Lans, R.G.J.M. (author), Haringa, C. (author), Noorman, H.J. (author), Picioreanu, C. (author)
Mass transfer limitations in syngas fermentation processes are mostly attributed to poor solubility of CO and H<sub>2</sub> in water. Despite these assumed limitations, a syngas fermentation process has recently been commercialized. Using large-sale external-loop gas-lift reactors (EL-GLR), CO-rich off-gases are converted into ethanol, with...
journal article 2022
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Dehdashti Akhavan, Navid (author), Abroug, Foued (author), Arnaud, Lionel (author), Hooman, K. (author)
High-pressure drops characteristic of microchannel heat sinks (MCHS) is an issue that needs to be addressed to reduce the size of heat-removing devices in compact electronic devices. Supercritical carbon dioxide (s-CO₂) is a suitable candidate being proposed as an alternative coolant to enhance the cooling of the microchannel heat sink (MCHS)...
journal article 2022
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van Sluis, M. (author), Nasrollahi, S. (author), Gangoli Rao, A. (author), Eitelberg, G. (author)
The AeroCity is a new form of transportation concept that has been developed to provide high-speed ground transportation at a much lower cost than the existing high-speed railway. Utilizing the Wing-in-Ground (WIG) effect, the AeroCity vehicle does not require complex infrastructures like other contemporary concepts, such as the Hyperloop or...
journal article 2022
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Foroozesh, Jamal (author), Hosseini, S. H. (author), Ahmadian Hosseini, A. J. (author), Parvaz, F. (author), Elsayed, K. (author), Uygur Babaoğlu, Nihan (author), Hooman, K. (author), Ahmadi, G. (author)
The rising energy demand for buildings has enhanced public awareness of sustainable energy sources and technologies. In particular, natural ventilation systems such as wind-catchers have attracted considerable new attention. A new wind-catcher design with single-stage direct-air evaporative cooling was proposed for indoor air conditioning. An...
journal article 2022
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Pál, Botond (author), Roekaerts, D.J.E.M. (author), Zandbergen, B.T.C. (author)
This study investigates the potential of a newly released multi-phase solver to simulate atomisation in an air-blast type atomiser. The 'VOF-to-DPM' solver was used to simulate primary and secondary atomisation in an atomiser with a coaxial injector-like geometry. The solver uses a hybrid Eulerian/Eulerian-Lagrangian formulation with...
journal article 2021
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