Turbulence Structure of a Liquid-Solid Two-Phase Jet by Means of Laser Techniques

Abstract

Characteristics on particle motion in a liquid-solid two-phase jet flow were studied in the paper. The water jet including glass particle of 389 μm in mean diameter was injected into water bath. The experimental conditions were 0.21% of initial particle volume ratio, 5mm in pipe diameter and 1.84 m/s of mean velocity on outlet of the jet. A laser Doppler anemometer (LDA) with size discrimination was applied for measuring the time serious velocities of the single-phase flow, particle and water phase flow. A particle image velocimetry (PIV) was also applied in the two-phase flow. The normal PIV method can hardly measure the particle size and perform the particle size discrimination. In the experiment, using the gray scales related with the scattering light intensity, measuring method with size discrimination in two-phase flow was carried out. The experimental results show less difference between velocities of single-phase flow and water-phase flow under this low particle volume ratio condition. Particles have the relative motion with the water-phase and large rms velocity. The PIV used in this experiment, which is called multi-intensity-layer-PIV: MILP, can measure water-phase velocity with good accuracy.

Numerical simulation of coaxial turbulent jet with and without discrete particles

“…8 that overall the difference between the dispersed phase and the single phase predictions is almost nil except a few regions near the inner shear layer at ɳ = 1.11. This is found to be consistent with the experimental observation by Arai et al [23], and later, Sadr and Klewicki [17], and Virdung and Rasmuson [8] wherein the effect of mass loading at 0.21% on the continuous phase was reported as insignificant. Figure 9 shows comparison of the axial turbulent intensity predicted along the radial direction with and without the dispersed phase.…”