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Inertial regimes in a channel flow of suspension of finite-size neutrally buoyant particles are studied for a wide range of Reynolds numbers: $500 \le Re\le 5000$, and particle volume fractions: $0 \le \Phi \le 0.3$. The flow is classified in three different regimes according to the phase-averaged stress budget across the channel \cite...conference paper 2015
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Breugem, W.P. (author)A second-order accurate and highly efficient Immersed Boundary Method (IBM) is presented for simulating flows along rectangular non-moving solid objects. In this method a rectangular object is placed on a staggered Cartesian grid such that its boundary coincides with grid points for the boundary-normal velocity component. By imposing forces at...conference paper 2006
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Lashgari, I. (author), Picano, F. (author), Breugem, W.P. (author), Brandt, L. (author)Inertial regimes in a channel flow of suspension of finite-size neutrally buoyant particles are studied for a wide range of Reynolds numbers: 500 Re 5000, and particle volume fractions: 0 0:3. The flow is classified in three different regimes according to the phase-averaged stress budget across the channel [2]. The laminar viscous regime at low...conference paper 2015
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Highly porous materials are found in various industrial applications and environmental flows. In previous studies it was found that a turbulent flow along a highly porous wall experiences a higher skin friction as compared to a solid wall with similar surface roughness when the so-called permeability Reynolds number (Re_K) is larger than O(1)....conference paper 2015
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Picano, F. (author), Costa, P. (author), Breugem, W.P. (author), Brandt, L. (author)Dense suspensions are usually investigated in the laminar limit where inertial effects are insignificant. When the flow rate is high enough, i.e. at high Reynolds number, the flow may become turbulent and the interaction between solid and liquid phases modifies the turbulence we know in single-phase fluids. In the present work, we study...conference paper 2015
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- Breugem, W.P. (author), Simões Costa, P. (author) conference paper 2013
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Benschop, H.O.G. (author), Westerweel, J. (author), Breugem, W.P. (author)The use of drag reducing surface textures is a promising passive method to reduce fuel consumption. Probably most wellknown is the utilisation of shark-skin inspired ridges or riblets parallel to the mean flow. They can reduce drag up to 10%. Recently another bio-inspired texture based on bird flight feather riblets has been proposed. It differs...conference paper 2015
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The use of drag reducing surface textures is a promising passive method to reduce fuel consumption. Probably most wellknown is the utilisation of shark-skin inspired ridges or riblets parallel to the mean flow. They can reduce drag up to 10%. Recently another bio-inspired texture based on bird flight feather riblets has been proposed. It differs...conference paper 2015
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Breugem, W.P. (author), Pourquie, M. (author), Boersma, B.J. (author)The Immersed Boundary Method (IBM) is a powerful method for simulating flows in complex geometries [1,2]. In this method complex geometries are embedded on a computational grid, which usually does not conform to the shape of the geometries. No boundary conditions are specified, but instead in the vicinity of solid boundaries forces are imposed...conference paper
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Dense suspensions are usually investigated in the laminar limit where inertial effects are insignificant. When the flow rate is high enough, i.e. at high Reynolds number, the flow may become turbulent and the interaction between solid and liquid phases modifies the turbulence we know in single-phase fluids. In the present work, we study...conference paper 2015
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Francesco, Picano (author), Breugem, W.P. (author), Luca, Brandt (author)Suspensions are often found in different processes and applications, e.g. sediment transport in environments or pharmaceutical engineering. The laminar regime in the semi-dilute or dense cases, non vanishing volume fraction, is usually characterized by the sometime spectacular rheological properties induced by the suspended phase. Much less...conference paper 2013
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Goudar Vishwanathappa, M. (author), Breugem, W.P. (author), Jodai, Y. (author), Elsinga, G.E. (author)For channel flow, we explore how the interaction of weak eddies produces additional eddies by means of auto-generation. This is done by DNS of two eddies with different initial strengths, initial sizes and initial stream-wise spacing between them. The numerical procedure followed is similar to Zhou et al[1]. The two eddies merge into a single...conference paper 2016
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Charruault, F.T. (author), Greidanus, A.J. (author), Breugem, W.P. (author), Westerweel, J. (author)The present study introduces an experimental technique based on a Free Surface-Synthetic Schlieren (FS-SS) method in order to characterize free surfaces subjected to strong deformations. Current synthetic Schlieren methods are based on local image correlation and thus limited to rather weak image deformations, implying that they can only resolve...conference paper 2018
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Goudar Vishwanathappa, M. (author), Breugem, W.P. (author), Elsinga, G.E. (author)For channel flow, we explore how a hairpin eddy may reach a threshold strength required to produce additional hairpins by means of auto-generation. This is done by studying the interaction of two eddies with different initial strengths (but both below the threshold strength), initial sizes and initial streamwise spacing between them. The...conference paper 2013
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Picano, Francesco (author), Simões Costa, P. (author), Breugem, W.P. (author), Brandt, Luca (author)Dense suspensions are usually investigated in the laminar limit where inertial effects are insignificant. In this regime, the main effect of the suspended phase is to alter the rheological behavior of the flow which always displays higher effective viscosity with respect to the carrier fluid. When the flow rate is high enough, i.e. at high...conference paper 2017
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Breugem, W.P. (author)The study of flows over permeable walls is relevant to many applications. Examples are flows over and through porous river beds, vegetation, snow, heat exchangers of foam metal, and oil wells. The main objectives of this thesis are to gain insight in the influence of wall permeability on both laminar and turbulent flows, and to develop a...doctoral thesis 2005
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Lambert, R.A. (author), Picano, F. (author), Breugem, W.P. (author), Brandt, L. (author)A numerical study of swimming particle motion and nutrient transport is conducted for a semidilute to dense suspension in a thin film. The steady squirmer model is used to represent the motion of living cells in suspension with the nutrient uptake by swimming particles modelled using a first-order kinetic equation representing the absorption...journal article 2013
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Breugem, W.P. (author), Boersma, B.J. (author)A direct numerical simulation (DNS) has been performed of turbulent channel flow over a three-dimensional Cartesian grid of 30×20×9 cubes in, respectively, the streamwise, spanwise, and wall-normal direction. The grid of cubes mimics a permeable wall with a porosity of 0.875. The flow field is resolved with 600×400×400 mesh points. To enforce...journal article 2005
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Lashgari, I. (author), Picano, F. (author), Breugem, W.P. (author), Brandt, L. (author)We study the transition from laminar to turbulent flow in a channel seeded with finite-size neutrally buoyant particles. A fixed ratio of 10 between the channel height and the particle diameter is considered. The flow is examined in the range of Reynolds numbers 500 ? Re ? 5000 and the particle volume fractions 0.001 ? ? ? 0.3. We report a non...journal article 2015
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Lashgari, I. (author), Picano, F. (author), Breugem, W.P. (author), Brandt, L. (author)The aim of this Letter is to characterize the flow regimes of suspensions of finite-size rigid particles in a viscous fluid at finite inertia. We explore the system behavior as a function of the particle volume fraction and the Reynolds number (the ratio of flow and particle inertia to viscous forces). Unlike single-phase flows, where a clear...journal article 2014