Primary cementing of horizontal wells. Displacement flows in eccentric horizontal annuli. Part 2. Computations

We present results of three-dimensional computational simulations of horizontal eccentric annular displacement flows as studied experimentally by Renteria & Frigaard (J. Fluid Mech., vol. 905, 2020, A7). We show the simulations are able to effectively capture detailed dispersive features of the flows, not resolved in simpler models. Top side flows, slumping flows and narrow side residual layers are predicted reliably and we are able to understand the main mechanisms that drive the flow into one of these classifications. Both experiments and simulations agree in their classification of steady and unsteady displacements. However, when the dispersion is properly resolved the concept of a steady state displacement becomes questionable. We study the axial spreading of the displacement front via one-dimensional simplifications, both advective and diffusive. While these do not fully describe the flows, they give some estimates that are useful for practical application.