Development of a novel hybrid discrete particle-immersed boundary model for fluidized bed membrane reactors

In recent years many different types of fluidized bed membrane reactors have been proposed, for example for the production of ultra-pure hydrogen. For the development and optimization of these novel fluidized bed membrane reactors, fundamental knowledge on the effect of the presence of – and permeation of gas through – the immersed membranes on the hydrodynamics and heat and mass transfer characteristics of the fluidized bed is essential, yet largely lacking in the literature.
In this work a hybrid 3D soft-sphere Discrete Particle - Immersed Boundary Model has been developed to investigate the hydrodynamics in great detail, specifically focusing on bubble formation/annihilation close to the submerged membranes, bubble size distribution and particle mixing as a function of the permeation ratio. In this paper, the details of the numerical implementation of the immersed boundary method are described and validated, and first results on the effect of gas extraction and gas addition through the membranes on the fluidized bed hydrodynamics are presented.