References of "Radl, Stefan"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailThe effect of liquid bridge model details on the dynamics of wet fluidized beds
Wu, Mingqiu UL; Khinast, Johannes; Radl, Stefan

in AIChE Journal (2018), 64(2), 437-456

Wet fluidized beds of particles in small periodic domains are simulated using the CFD-DEM approach. A liquid bridge is formed upon particle-particle collisions, which then ruptures when the particle ... [more ▼]

Wet fluidized beds of particles in small periodic domains are simulated using the CFD-DEM approach. A liquid bridge is formed upon particle-particle collisions, which then ruptures when the particle separation exceeds a critical distance. The simulations take into account both surface tension and viscous forces due to the liquid bridge. We perform a series of simulations based on different liquid bridge formation models: (1) the static bridge model of Shi and McCarthy, (2) a simple static version of the model of Wu et al., as well as (3) the full dynamic bridge model of Wu et al. We systematically compare the differences caused by different liquid bridge formation models, as well as their sensitivity to system parameters. Finally, we provide recommendations for which systems a dynamic liquid bridge model must be used, and for which application this appears to be less important [less ▲]

Detailed reference viewed: 106 (29 UL)
Full Text
Peer Reviewed
See detailLiquid transport rates during binary collisions of unequally-sized particles
Wu, Mingqiu UL; Johannes, Johannes; Radl, Stefan

in Powder Technology (2017), 309(1), 95-109

In this paper, we study the liquid transport between particles of different sizes, as well as build a dynamic liquid bridge model to predict liquid transport between these two particles. Specifically, the ... [more ▼]

In this paper, we study the liquid transport between particles of different sizes, as well as build a dynamic liquid bridge model to predict liquid transport between these two particles. Specifically, the drainage process of liquid adhering to two unequally-sized, non-porous wet particles is simulated using direct numerical simulations (DNS). Same as in our previous work (Wu et al., AIChE Journal, 2016, 62:1877–1897), we first provide an analytical solution of a proposed dynamic liquid bridge model. We find that such an analytical solution also describes liquid transport during collisions of unequally-sized particles very well. Finally, we show that our proposed model structure is sufficient to collapse all our direct numerical simulation data. Our model is hence able to predict liquid transport rates in size-polydisperse systems for a wide range of parameters [less ▲]

Detailed reference viewed: 91 (12 UL)
See detailLiquid Transport in Bi-disperse Particle Beds
Wu, Mingqiu UL; Khinast, Khinast; Radl, Stefan

Poster (2016, September 15)

Flow of highly saturated wet granular matter is encountered in wide range of engineering application, particularly in the pharmaceutics, food industry and energy sector , in addition, granular particles ... [more ▼]

Flow of highly saturated wet granular matter is encountered in wide range of engineering application, particularly in the pharmaceutics, food industry and energy sector , in addition, granular particles beds usually compose of various of particle properties (i.e.,, shape, size, density, etc.) and it well know that particle size polydispersity and shape significantly influence on the transport of mass and liquid in a fluidized bed system. [less ▲]

Detailed reference viewed: 35 (4 UL)
Full Text
Peer Reviewed
See detailA Model to Predict Liquid Bridge Formation Between Wet Particles Based on Direct Numerical Simulations
Wu, Mingqiu UL; Khinast, Johannes; Radl, Stefan

in AIChE Journal (2016), 62(6), 1877-1987

We study dynamic liquid bridge formation, which is relevant for wet granular flows involving highly viscous liquids and short collisions. Specifically, the drainage process of liquid adhering to two ... [more ▼]

We study dynamic liquid bridge formation, which is relevant for wet granular flows involving highly viscous liquids and short collisions. Specifically, the drainage process of liquid adhering to two identical, non-porous wet particles with different initial film heights is simulated using Direct Numerical Simulations (DNS). We extract the position of the interface, and define the liquid bridge and its volume by detecting a characteristic neck position. This allows us building a dynamic model for predicting bridge volume, and the liquid remaining on the particle surface. Our model is based on two dimensionless mobility parameters, as well as a dimensionless time scale to describe the filling process. In the present work model parameters were calibrated with DNS data. We find that the proposed model structure is sufficient to collapse all our simulation data, indicating that our model is general enough to describe liquid bridge formation between equally sized particles [less ▲]

Detailed reference viewed: 117 (6 UL)