Numerical simulation of non-Newtonian hydrodynamics in an annular channel with tool joint

The paper presents the simulations of the local and integral characteristics of an annular flow with tool joints, depending on problem parameters. The structure of the flow in the vicinity of the coupling, in the areas of stagnant and reverse flow, is studied in detail. The characteristic length of separation and stabilization zones, i.e. the distance behind the joint where the flow reaches steady-state again is investigated. The sizes of pipes and tool joints in the study match those used while drilling. The numerical modelling is performed in 3D steady-state formulation for both laminar and turbulent regimes using original in-house software.