Velocity and Momentum Decay Characteristics of Submerged Yield-Pseudoplastic Jets Available to Purchase

The velocity and momentum decay characteristics of submerged yield-pseudoplastic jets are studied. Numerical solutions to the governing mass and momentum conservation equations, along with the Herschel-Bulkley rheological model, are obtained using a finite-difference scheme. A parametric study is implemented to investigate the influence of flow inertia and rheology over the following range of parameters: Reynolds number, 50 ≤ Re ≤ 200, Yield number, 0 ≤ Y ≤ 1, and shear-thinning index, 0.6 ≤ n ≤ 1. A large recirculation region exists for Newtonian and pseudoplastic non-Newtonian jets. However, the extent and strength of the recirculation region substantially diminish with the yield number and, to a lesser extent, when the shear-thinning index is reduced from 1 to 0.6. Increasing the yield number beyond a critical value eliminates flow recirculation. The centerline velocity and momentum decay of yield-pseudoplastic jets, in general, increases with the yield number. Velocity and momentum based depths of penetration, DPU and DPM, respectively, are extracted and presented. A substantial decrease in DPU and DPM is observed when the shear-thinning index is reduced from 1 to 0.6 for Y = 0. The presence of yield stress significantly reduces both DPU and DPM of submerged jets. The impact of shear-thinning on the decay characteristics of the jet is more pronounced at low yield numbers.