2D rotation of rigid inclusions in confined bulk simple shear flow: a numerical study

We have used incompressible Navier–Stokes in 2D finite element modelling to investigate rigid inclusion rotation under confined bulk simple shear flow. Confinement is defined as the ratio (S) between the channel width (H) and the inclusion's least axis (e2)(S=H/e2). The numerical results show that (i) inclusion rotation is strongly influenced by S and, when the confinement is effective, aspect ratio (R) and shape also play an important role. (ii) Back rotation is limited because inclusions reach a stable equilibrium orientation (ϕse). (iii) There is also an unstable equilibrium orientation (ϕue), which defines an antithetic rotation field with ϕse, and both ϕse and ϕue depend on S, and inclusion R and shape.