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Soft-glassy materials are a class of material showing a solid-like behavior at rest and local yielding when subject to a high enough stress. While systems like foams, emulsions, colloidal and polymer gels have been widely studied in the last decades[1-2], still little is known about the flow behavior of dense suspensions (volume concentration above 0.6) of polymeric coated core-shells, i.e. capsules [3]. The rheology of capsules for volume fractions up to 0.9 is investigated numerically under inhomogeneous (Kolmogorov and Poiseuille) and homogeneous (shear) flows using the lattice Boltzmann method (BGK D3Q19) [4]. The fluid-interface coupling is achieved using the immersed boundary method and forces are computed on the surface of the capsules using a finite element scheme [5]. This study includes the effect of the mechanical properties of the individual capsules (stiffness/softness) on the local and global rheological behavior. Furthermore, the fluid-jammed phase transition is discussed for several sets of parameters.
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