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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

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Effect of viscosity on droplet-droplet collisional interaction

Finotello, Giulia (author), Padding, J.T. (author), Deen, Niels G. (author), Jongsma, Alfred (author), Innings, Fredrik (author), Kuipers, J.A.M. (author)

A complete knowledge of the effect of droplet viscosity on droplet-droplet collision outcomes is essential for industrial processes such as spray drying. When droplets with dispersed solids are dried, the apparent viscosity of the dispersed phase increases by many orders of magnitude, which drastically changes the outcome of a droplet-droplet...

journal article 2017

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Particle-based modeling of heterogeneous chemical kinetics including mass transfer

Sengar, A. (author), Kuipers, J.R. (author), Van Santen, Rutger A. (author), Padding, J.T. (author)

Connecting the macroscopic world of continuous fields to the microscopic world of discrete molecular events is important for understanding several phenomena occurring at physical boundaries of systems. An important example is heterogeneous catalysis, where reactions take place at active surfaces, but the effective reaction rates are...

journal article 2017

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Three-dimensional fluidized beds with rough spheres: Validation of a Two Fluid Model by Magnetic Particle Tracking and discrete particle simulations

Yang, L. (author), Padding, J.T. (author), Buist, K. A. (author), Kuipers, J.R. (author)

Two fluid model simulations based on our recently introduced kinetic theory of granular flow (KTGF) for rough spheres and rough walls, are validated for the first time for full three-dimensional (3D) bubbling fluidized beds. The validation is performed by comparing with experimental data from Magnetic Particle Tracking and more detailed...

journal article 2017

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Viscoelastic flow simulations in random porous media

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

We investigate creeping flow of a viscoelastic fluid through a three dimensional random porous medium using computational fluid dynamics. The simulations are performed using a finite volume methodology with a staggered grid. The no slip boundary condition on the fluid-solid interface is implemented using a second order finite volume immersed...

journal article 2017

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Magnetic particle tracking for nonspherical particles in a cylindrical fluidized bed

Buist, Kay A. (author), Jayaprakas, Pavithra (author), Kuipers, J.A.M. (author), Deen, Niels G. (author), Padding, J.T. (author)

In granular flow operations, often particles are nonspherical. This has inspired a vast amount of research in understanding the behavior of these particles. Various models are being developed to study the hydrodynamics involving nonspherical particles. Experiments however are often limited to obtain data on the translational motion only. This...

journal article 2017

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Fluidization of spherocylindrical particles

Mahajan, V.V. (author), Nijssen, Tim M.J. (author), Fitzgerald, B. (author), Hofman, Jeroen (author), Kuipers, Hans (author), Padding, J.T. (author)

Multiphase (gas-solid) flows are encountered in numerous industrial applications such as pharmaceutical, food, agricultural processing and energy generation. A coupled computational fluid dynamics (CFD) and discrete element method (DEM) approach is a popular way to study such flows at a particle scale. However, most of these studies deal with...

journal article 2017

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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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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