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Lift-off of multiple particles in a narrow channel

Maitri, R. V. (author), Padding, J.T. (author), Kuipers, J. A.M. (author), Peters, E. A.J.F. (author)

In this work, we perform simulations of particle laden flow in a wide and long narrow channel in a Newtonian fluid. Simulations are performed for mono-sized and equal density spheres with varying Archimedes and Reynolds number. In the simulations, different phases of particle transport - rolling, saltation and suspension are observed. During...

journal article 2020

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Fluidization of spherical versus elongated particles: Experimental investigation using magnetic particle tracking

Mema, I. (author), Buist, Kay A. (author), Kuipers, J. A.M. (author), Padding, J.T. (author)

In biomass processing fluidized beds are used to process granular materials where particles typically possess elongated shapes. However, for simplicity, in computer simulations particles are often considered spherical, even though elongated particles experience more complex particle–particle interactions as well as different hydrodynamic...

journal article 2020

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Parallelization of a stochastic Euler-Lagrange model applied to large scale dense bubbly flows

Kamath, S. (author), Masterov, M. V. (author), Padding, J.T. (author), Buist, K. A. (author), Baltussen, M. W. (author), Kuipers, J. A.M. (author)

A parallel and scalable stochastic Direct Simulation Monte Carlo (DSMC) method applied to large-scale dense bubbly flows is reported in this paper. The DSMC method is applied to speed up the bubble-bubble collision handling relative to the Discrete Bubble Model proposed by Darmana et al. (2006) [1]. The DSMC algorithm has been modified and...

journal article 2020

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Towards a particle based approach for multiscale modeling of heterogeneous catalytic reactors

Sengar, A. (author), Kuipers, J. A.M. (author), van Santen, R. A. (author), Padding, J.T. (author)

Particle based approaches are one of the recent modeling techniques to overcome the computational limitation in multiscale modeling of complex processes, for example a heterogeneous catalytic reactor. We propose an efficient model for a chemical reactor where hydrodynamics of the solvent is determined by Stochastic Rotation Dynamics and a...

journal article 2019

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Droplet collisions of water and milk in a spray with Langevin turbulence dispersion

Finotello, Giulia (author), Padding, J.T. (author), Buist, Kay A. (author), Jongsma, Alfred (author), Innings, Fredrik (author), Kuipers, J. A.M. (author)

In this work we investigate droplet-droplet collision interactions in a spray system using an Eulerian-Lagrangian model with subgrid turbulence dispersion. The effect of different droplet viscosities on the type and frequency of droplet collision is investigated, knowledge of which is essential for industrial processes such as spray drying...

journal article 2019

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Effect of microchannel structure and fluid properties on non-inertial particle migration

Maitri, R. V. (author), De, S. (author), Koesen, S. P. (author), Wyss, H. M. (author), van der Schaaf, J. (author), Kuipers, J. A.M. (author), Padding, J.T. (author), Peters, E.A.J.F. (author)

In this work, we investigate the influence of channel structure and fluid rheology on non-inertial migration of non-Brownian polystyrene beads. Particle migration in this regime can be found in biomedical, chemical, environmental and geological applications. However, the effect of fluid rheology on particle migration in porous media remains...

journal article 2019

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Numerical investigation of droplet-droplet collisions in a water and milk spray with coupled heat and mass transfer

Finotello, Giulia (author), Padding, J.T. (author), Buist, Kay A. (author), Schijve, Annelien (author), Jongsma, Alfred (author), Innings, Fredrik (author), Kuipers, J.A.M. (author)

Large scale simulation models can aid in improving the design of spray dryers. In this work an Eulerian-Lagrangian model with coupled gas phase and droplet heat and mass transfer balances is used to study airflow dynamics, temperature and humidity profiles at different positions in the spray. The turbulent gas flow is solved using large eddy...

journal article 2019

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The dynamics of milk droplet–droplet collisions

Finotello, Giulia (author), Kooiman, Roeland F. (author), Padding, J.T. (author), Buist, Kay A. (author), Jongsma, Alfred (author), Innings, Fredrik (author), Kuipers, J. A.M. (author)

Spray drying is an important industrial process to produce powdered milk, in which concentrated milk is atomized into small droplets and dried with hot gas. The characteristics of the produced milk powder are largely affected by agglomeration, combination of dry and partially dry particles, which in turn depends on the outcome of a collision...

journal article 2018

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Nonspherical particles in a pseudo-2D fluidized bed: Experimental study

Mahajan, V.V. (author), Padding, J.T. (author), Nijssen, Tim M.J. (author), Buist, Kay A. (author), Kuipers, J.R. (author)

Fluidization is widely used in industries and has been extensively studied, both experimentally and theoretically, in the past. However, most of these studies focus on spherical particles while in practice granules are rarely spherical. Particle shape can have a significant effect on fluidization characteristics. It is therefore important to...

journal article 2018

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Stochastic DSMC method for dense bubbly flows: Methodology

Kamath, S. (author), Padding, J.T. (author), Buist, K. A. (author), Kuipers, J.R. (author)

A stochastic Direct Simulation Monte Carlo (DSMC) method has been extended for handling bubble-bubble and bubble-wall collisions. Bubbly flows are generally characterized by highly correlated velocities due to presence of the surrounding liquid. The DSMC method has been improved to account for these kind of correlated collisions along with a...

journal article 2018

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A granular Discrete Element Method for arbitrary convex particle shapes: Method and packing generation

Seelen, L. J.H. (author), Padding, J.T. (author), Kuipers, J.R. (author)

A novel granular discrete element method (DEM) is introduced to simulate mixtures of particles of any convex shape. To quickly identify pairs of particles in contact, the method first uses a broad-phase and a narrow-phase contact detection strategy. After this, a contact resolution phase finds the contact normal and penetration depth. A new...

journal article 2018

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Drag, lift and torque correlations for non-spherical particles from Stokes limit to high Reynolds numbers

Pacha Sanjeevi, S.K. (author), Kuipers, J. A.M. (author), Padding, J.T. (author)

Accurate direct numerical simulations are performed to determine the drag, lift and torque coefficients of non-spherical particles. The numerical simulations are performed using the lattice Boltzmann method with multi-relaxation time. The motivation for this work is the need for accurate drag, lift and torque correlations for high Re regimes,...

journal article 2018

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Experimental investigation of non-Newtonian droplet collisions: the role of extensional viscosity

Finotello, Giulia (author), De, Shauvik (author), Vrouwenvelder, Jeroen C.R. (author), Padding, J.T. (author), Buist, Kay A. (author), Jongsma, Alfred (author), Innings, Fredrik (author), Kuipers, J. A.M. (author)

We investigate the collision behaviour of a shear thinning non-Newtonian fluid xanthan, by binary droplet collision experiments. Droplet collisions of non-Newtonian fluids are more complex than their Newtonian counterpart as the viscosity no longer remains constant during the collision process. Despite the complex collision dynamics, we are...

journal article 2018

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An improved ghost-cell sharp interface immersed boundary method with direct forcing for particle laden flows

Maitri, R.V. (author), Das, S. (author), Kuipers, J.A.M. (author), Padding, J.T. (author), Peters, E.A.J.F. (author)

In this paper, an accurate and stable sharp interface immersed boundary method(IBM) is presented for the direct numerical simulation of particle laden flows. The current IBM method is based on the direct-forcing method by incorporating the ghost-cell approach implicitly. An important feature of this IBM is the sharp representation of the solid...

journal article 2018

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Deactivation kinetics of solid acid catalyst with laterally interacting protons

Sengar, A. (author), Van Santen, Rutger A. (author), Steur, E. (author), Kuipers, J.A.M. (author), Padding, J.T. (author)

journal article 2018

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Non-spherical particles in a pseudo-2D fluidised bed: Modelling study

Mahajan, V.V. (author), Nijssen, Tim M.J. (author), Kuipers, J.R. (author), Padding, J.T. (author)

Fluidised beds are used in a variety of processes because of their favourable mass and heat transfer characteristics. In this and many other processes, non-spherical particles are commonplace, which can drastically affect the fluidisation behaviour. In this study, we use numerical models to study non-spherical fluidisation behaviour in detail...

journal article 2018

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Viscoelastic effects on residual oil distribution in flows through pillared microchannels

De, S. (author), Krishnan, P. (author), van der Schaaf, J. (author), Kuipers, J. A.M. (author), Peters, E. A.J.F. (author), Padding, J.T. (author)

Hypothesis Multiphase flow through porous media is important in a number of industrial, natural and biological processes. One application is enhanced oil recovery (EOR), where a resident oil phase is displaced by a Newtonian or polymeric fluid. In EOR, the two-phase immiscible displacement through heterogonous porous media is usually governed...

journal article 2018

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Experimental study on orientation and de-mixing phenomena of elongated particles in gas-fluidized beds

Boer, L. (author), Buist, K. A. (author), Deen, N. G. (author), Padding, J.T. (author), Kuipers, J. A.M. (author)

In this experimental study the segregation behavior for fluidized mixtures of spherical and cylindrical particles is investigated. In industry, fluidization of particles featuring a wide range of shapes is common in various applications such as biomass gasification, drying applications, food processing and production of pharmaceuticals....

journal article 2018

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Viscoelastic flow past mono- and bidisperse random arrays of cylinders: flow resistance, topology and normal stress distribution

De, Sourav (author), Kuipers, J.A.M. (author), Peters, E.A.J.F. (author), Padding, J.T. (author)

We investigate creeping viscoelastic fluid flow through two-dimensional porous media consisting of random arrangements of monodisperse and bidisperse cylinders, using our finite volume-immersed boundary method introduced in S. De, et al., J. Non-Newtonian Fluid Mech., 2016, 232, 67–76. The viscoelastic fluid is modeled with a FENE-P model. The...

journal article 2017

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A coupled Volume of Fluid and Immersed Boundary Method for simulating 3D multiphase flows with contact line dynamics in complex geometries

Patel, H.V. (author), Das, S. (author), Kuipers, J.A.M. (author), Padding, J.T. (author), Peters, E.A.J.F. (author)

journal article 2017