Numerical Investigation on Effect of Tip Angle on Settling of a Conical Shape Particle

Transport and sedimentation of spherical and non-spherical solid particles in quiescent fluids play significant roles in many separation processes and powder industries. Current work investigates the spherical and conical shape falling solid particles in a stationary viscous fluid. First, the flow around a falling solid sphere was simulated and the results were compared with the experimental data and empirical correlations. Then, the flow around conical shaped particles with the same volume and different aspect ratios were analyzed. The simulation results were presented for different Reynolds numbers, Re, aspect ratios, λ, and sphericity, ψ. Recirculation zone was generated above the particle in low-viscosity fluid environments. The simulation results showed that the length of the wake region was increased by reduction of viscosity (increase or Reynolds number). Also for conical particles, higher sphericity caused smaller drag coefficient and increase of tip angle, increased the drag coefficient. Correlations were presented for drag coefficients for particles, based on the Reynolds number and aspect ratio.