Experimental and numerical investigation of downward gas-dispersed turbulent pipe flow

Results of experimental and numerical simulations of the downward turbulent gas flow laden with dispersed solid particles in a vertical pipe are presented. The influence of the particles on the turbulence was studied at moderate particle concentrations. The radial profiles of the axial and radial velocity components and of the turbulent kinetic energy of the carrier (gas) and the dispersed phases (50 μm spherical glass particles) were measured using two-component laser Doppler anemometer (LDA). Calculations were performed at both experimental and superset conditions with various size and material of particles. The mathematical formulation employs a set of equations in Euler variables for description of the transport processes in the fluid and disperse phases. The addition of particles into a turbulent carrier flow decreases the level of turbulence of the gas phase because of particles involvement into fluctuation motion. A significant anisotropy of fluctuations of the particle velocity is found. The amplitude of turbulent fluctuations of particle velocity in the axial direction is much higher than that in the radial direction.