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Item type:Publication, Access status: without files , Intensification of Fluidized-Bed Processes for Drying and Formulation(2014-03-17); ; ; ; Publicationtype: Book Part20 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 31 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 23 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Magnetic monitoring of a single particle in a prismatic spouted bed(2009-09-23); ; ; In this work a non-intrusive measuring technique for continuous tracking of a magnetic marked particle during fluidization in a prismatic spouted bed is presented. The magnetic monitoring system provides besides the spatial coordinates x, y and z the orientation of the particle, whereby the trajectory, the velocity, the acceleration as well as the rotation of the particle are obtained. It will be demonstrated that the characteristic particle trajectories and particle velocity distributions in dependency of the gas throughput and of the bed mass can be detected in this type of spouted bed. Furthermore, a calculated particle velocity distribution obtained by a CFD continuum simulation will be favorably compared with a measured distribution.Publicationtype: Journal Article17 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Characterization and CFD-modeling of the hydrodynamics of a prismatic spouted bed apparatus(2009-07-15); ; ; ; Recently the importance of spouted bed technology has significantly increased in the context of drying processes as well as granulation, agglomeration or coating processes. However, the understanding of the complex interactions within and between the single phases is still low and needs further improvement. Several research groups apply both continuum as well as discrete element simulations to understand the hydrodynamics of the spouting process. This work focuses on the simulation of the hydrodynamic behavior of a prismatic spouted bed apparatus by applying the Euler/Euler continuum approach in the commercial computational fluid dynamics (CFD) software package FLUENT 6.2. The simulations are validated by experiments. Calculated and experimental (by PIV-measurements) obtained velocity vector maps, as well as measured and calculated gas phase pressure fluctuations over the entire bed are compared. The aim of this work is to improve the understanding of the hydrodynamics of the spouting process.Publicationtype: Journal Article29 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Three-dimensional computational fluid dynamics modeling of a prismatic spouted bed(2009-05-20); ; ; ; Modern simulation tools like discrete particle models or continuum models have been established as precious methods to gain insight into the complex processes in fluidized and spouted beds. Valuable information on parameters influencing the hydrodynamics can be obtained directly from computer simulations. Numerous researchers applied two-dimensional discrete and continuum models to simulate fluidized and spouted beds. However, only few publications deal with three-dimensional continuum simulations, and very often results of three-dimensional experiments are compared with two-dimensional results. In this work, a three-dimensional simulation by application of a continuum model is presented in a prismatic spouted bed with slit-shaped gas inlets. Comparisons with two-dimensional simulations in the same geometry (Gryczka et al. 2009, Chem. Eng. Sci., in press) are also part of this publication. The influence of the third dimension on the hydrodynamic behavior (bubble formation, bubble size, etc.) will be discussed. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.Publicationtype: Journal Article21 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Controlled addition of reactants in a fluidized bed membrane reactor(2008-05); ; ; The focus of this contribution was to evaluate the membrane reactor concept in fluidized beds. The performance of a pilot-plant fluidized bed membrane reactor (FLBMR) was studied experimentally in comparison to the conventional operation as a fluidized bed reactor (FLBR). As model reaction was applied the catalytic oxidative dehydrogenation of ethane using a γ-alumina supported vanadium oxide catalyst. The beneficial effect of oxidant dosing over the membrane is most pronounced at high temperatures and long contact times.Publicationtype: Conference Paper30 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Characterization of the pneumatic behavior of a novel spouted bed apparatus(2008-05); ; ; ; Recently the importance of spouted bed technology has significantly increased in the context of drying processes as well as granulation, agglomeration or coating processes. Par-ticulate systems concerning very fine or non spherical particles that are difficult to fluidize, often cannot be treated in conventional fluidized beds. In contrast to those fluidized beds, the spouted bed technology with its specific flow structure offers the opportunity of stable fluidization under controlled conditions. Within this work the fluid dynamics of a novel spouted bed with two adjustable gas inlets is investigated. By analysis of gas fluctuation spectra by means of a fast Fourier transformation algorithm, different operation regimes are identified and depicted graphically. Furthermore, continuum CFD-modeling of the granular solid phase motion by means of an Euler/Euler approach and comparisons with experimental obtained velocity vector fields by means of particle image velocimetry (PIV) measurements will be presented in this work.Publicationtype: Conference Paper10 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Characterization of the pneumatic behavior of a novel spouted bed apparatus with two adjustable gas inlets(2008-02); ; ; ; Recently the importance of spouted bed technology has significantly increased in the context of drying processes as well as granulation, agglomeration or coating processes. Within this work the fluid dynamics of a novel spouted bed plant with two adjustable gas inlets is investigated. By analysis of gas phase pressure fluctuation spectra by means of fast Fourier transformation algorithm and quantitative particle image velocimetry (PIV) measurements, different operation ranges will be identified and depicted graphically. A stable spouting range will be identified if a uniform and circulating particle motion without occurrence of dead zones is observable resulting in equal gas phase pressure fluctuations. Particle velocity vector maps as well as root mean square (rms) velocity plots provided by the PIV measurements confirm the results of the determination of the stable spouting range by analysis of the gas phase pressure fluctuations.Publicationtype: Journal Article16 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 40