RSA CE&C 2015-2021 Group descriptions

30 There was special attention to the interplay of flow & mass, momentum and heat exchange in dense dispersed multiphase flows. As part of the ERC advanced grant MultiscaleFlows, awarded to J.A.M. Kuipers, a novel kinetic theory-based continuum model for dense gas- particle flows has been developed. 1,2 Particle-resolved DNS simulations were performed of gas-particle flows 3–6 and gas-liquid-solid flows. 7 Important advances were made in the detailed simulation of droplet and bubble dynamics using local-front reconstruction methods 8,9 in research funded by the TOP grant ‘First-principles based multi-scale modelling of transport in reactive three-phase flows’. We developed a massively parallel code for large-scale simulations of bubble columns and other dispersed flows. 10,11 Details of droplet-droplet collisions with applications for spray drying were elucidated. 12,13 Heat transfer and cooling through the presence of liquid was studied for fluidized beds using CFD-DEM 14–16 and also particle-resolved. 17 CFD-DEM simulations provided insight into mass transfer limitation due to particle clustering in riser flow. 18 To investigate mass transfer in thin boundary layers at bubble surfaces, both adaptive-mesh techniques 19 and special boundary layer approximations 20 were developed. 2. Single phase and multiphase flows in porous media Extensive studies have been performed on single-phase Newtonian flow in packed beds of non-porous spherical 21 and porous non-spherical particles 22 as well as non-Newtonian (i.e., viscoelastic) flow in porous media. 23 For slender-packed beds, as these occur in tubular reactors, particle-resolved predictive tools were developed for fluid-particle heat transfer 24 , wall-to-bed heat transfer 21 ,mass transfer coupled to surface reaction 25 and reactivenon-adiabatic cases. 26,27 Such systems are frequently encountered in catalytic conversions and display enormous complexity due to the wide range of time and length scales which need to be considered. In addition, novel powerful hybrid computational techniques such as a combined volume of fluid + immersed boundary method (VOF-IBM) have been developed 28 and validated to conduct extensive pore-resolved simulations of multiphase flow in porous media. 29 3. Non-invasive monitoring of multiphase flows In many processes involving catalytic conversions, dense granular flows are encountered. To study such systems, a magnetic particle tracking (MPT) technique was developed as part of the ERC advanced grant MultiscaleFlows to enable the simultaneous measurement of translational and rotational particle motion 30,31 in dense granular flows, providing powerful information for model validation. Particle image velocimetry-digital image analysis (PIV-DIA) was also applied to investigate the formation of particle clusters in riser flow 32 and to study the fluidization of non-spherical particles. 33 In addition, an integrated infrared thermography (PIV-DIA-IRT) technique has been developed, enabling the simultaneous measurement of flow and heat transfer in dense gas-fluidized beds. 34,35 A dual-emission laser-induced fluorescence (LIF) technique 36 has also been developed to measure pH and species concentration distributions in the wake of rising gas bubbles. Finally, a state-of-the-art MRI flow imaging facility was recently established in our laboratory, enabling the non-invasive monitoring of transport processes in multiphase reactors such as packed bed reactors. 37 Valorization and societal impact The valorization and societal impact of the research in our research group is visible through the research themes, which have a strong relationship with and impact on the performance of multiphase chemical reactors used in the process industries. Specifically, our research impacts society through: 1. Collaboration with the process industry in the form of bilateral projects, Industrial Partnership Programs (IPPs) and projects executed within the ARC CBBC consortium with leading companies in the chemical process industry.