<p>High wall shear stress and uneven gas-liquid mixing constrain anode slime side-blown smelting. A multi-fluid VOF model is developed to quantify the response of bath agitation and wall shear stress to lance inclination, bath depth, and injection velocity. Melt viscosity (0.2 Pa·s) was measured at 1573.15 K, and a 580 K inlet temperature was derived from conjugate heat transfer analysis. Simulations were performed for inclinations of −30° to +30°, depths of 1200–1800 mm, and velocities of 300–450 m·s⁻¹. Results show that a −15° inclination opposes buoyancy, lengthening the plume path and thickening the near-wall protective film from 8 mm (at −30°) to 40 mm, avoiding direct sidewall impingement. Increasing bath depth to 1800 mm enhances melt velocity, but the protective film thins to 22.5 mm at 1400 mm, shifting high-shear zones upward. Beyond 400 m·s⁻¹, jet inertia forms a central gas column; increasing velocity from 400 to 450 m·s⁻¹ raises melt velocity by only 11.6% while lance-tip shear stress jumps 18%. Conclusively, a shallow downward inclination (−15°) with velocities ⩽ 400 m·s⁻¹ optimizes agitation while mitigating localized high shear.</p>