The flow behavior of a confined viscoplastic non-Newtonian jet is investigated numerically within the steady laminar flow regime. The Bingham constitutive equation is used to model the rheology of interest. A parametric study is implemented to investigate the influence of confinement ratio and rheology over the following range of parameters: Confinement ratio, CR = {5, 10, 20}, and Yield number, Y = {0, 0.5, 2}. A large corner recirculation region typically characterizes the flow of a confined Newtonian jet. However, in the case of a Bingham viscoplastic jet, once a critical yield number is exceeded, flow recirculation is eliminated and a stagnant corner region is formed. The confinement ratio has a dramatic impact on the recirculation intensity and the evolution characteristics of the jet only in the case of Newtonian flows, i.e. Y = 0. In general, a more intense recirculation is associated with higher confinement ratios. The extent and the strength of flow recirculation are found to significantly diminish with the yield number. The axial penetration of the confined jet substantially increases with the confinement ratio for Newtonian fluids only and decreases with the yield numbers for all confinement ratios.
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