Particle velocity detection and measurement in two-phase flow using combined electronic logic system and LDA technique

Experimental data for solid–liquid flows at intermediate and high Stokes numbers

“…Increasing solids fraction leads to an increase in the drag force on the particles, propelling the particle motion in the streamwise direction, as has been observed in other experiments (Tsuji et al 1984). However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200.…”

“…However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200. The data from Lee & Durst (1982) were for lower concentrations and Reynolds number (0.06 % v/v and Re = 8000).…”

“…In the case of the results presented in figure 15, the observed enhancement of solid axial fluctuations with increasing solids concentration is likely to be due to (iii) the effect of the enhanced fluid fluctuations. Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations.…”

“…Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations. Figure 15(b,c) shows that the radial and theta components of the solids velocity fluctuations present no significant influence of the particle concentration at these conditions.…”

Experimental data for solid–liquid flows at intermediate and high Stokes numbers

“…Increasing solids fraction leads to an increase in the drag force on the particles, propelling the particle motion in the streamwise direction, as has been observed in other experiments (Tsuji et al 1984). However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200.…”

“…However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200. The data from Lee & Durst (1982) were for lower concentrations and Reynolds number (0.06 % v/v and Re = 8000).…”

“…In the case of the results presented in figure 15, the observed enhancement of solid axial fluctuations with increasing solids concentration is likely to be due to (iii) the effect of the enhanced fluid fluctuations. Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations.…”

“…Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations. Figure 15(b,c) shows that the radial and theta components of the solids velocity fluctuations present no significant influence of the particle concentration at these conditions.…”

A review of turbulence measurement techniques for flotation

“…However, some researchers have also applied the technique to study multiphase flows using LDA or PDA (an extension of LDA). One of these studies involved using a LDA device incorporating an electronic logic system to distinguish signals from water and solid particles in a low solid volumetric concentration (less than 2%) two phase system (solid-liquid suspension) (Sad Chemloul and Benmedjedi, 2010). The beauty of their approach was that electronic logic was employed to speed up the signal processing but unfortunately it was not sufficient to overcome LDA's intrinsic sensitivity to solid concentration.…”

Experimental data for solid–liquid flows at intermediate and high Stokes numbers

“…Increasing solids fraction leads to an increase in the drag force on the particles, propelling the particle motion in the streamwise direction, as has been observed in other experiments (Tsuji et al 1984). However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200.…”

“…However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200. The data from Lee & Durst (1982) were for lower concentrations and Reynolds number (0.06 % v/v and Re = 8000).…”

“…In the case of the results presented in figure 15, the observed enhancement of solid axial fluctuations with increasing solids concentration is likely to be due to (iii) the effect of the enhanced fluid fluctuations. Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations.…”

“…Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations. Figure 15(b,c) shows that the radial and theta components of the solids velocity fluctuations present no significant influence of the particle concentration at these conditions.…”

A review of turbulence measurement techniques for flotation

“…However, some researchers have also applied the technique to study multiphase flows using LDA or PDA (an extension of LDA). One of these studies involved using a LDA device incorporating an electronic logic system to distinguish signals from water and solid particles in a low solid volumetric concentration (less than 2%) two phase system (solid-liquid suspension) (Sad Chemloul and Benmedjedi, 2010). The beauty of their approach was that electronic logic was employed to speed up the signal processing but unfortunately it was not sufficient to overcome LDA's intrinsic sensitivity to solid concentration.…”

Experimental data for solid–liquid flows at intermediate and high Stokes numbers

“…Increasing solids fraction leads to an increase in the drag force on the particles, propelling the particle motion in the streamwise direction, as has been observed in other experiments (Tsuji et al 1984). However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200.…”

“…However, Lee & Durst (1982) and Chemloul & Benmedjedi (2010) measured increasing relative velocities with increasing concentrations. The data from Chemloul & Benmedjedi (2010) were taken in a similar range of concentrations as the present data but at a lower Reynolds number of 16 200. The data from Lee & Durst (1982) were for lower concentrations and Reynolds number (0.06 % v/v and Re = 8000).…”

“…In the case of the results presented in figure 15, the observed enhancement of solid axial fluctuations with increasing solids concentration is likely to be due to (iii) the effect of the enhanced fluid fluctuations. Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations.…”

“…Hardalupas et al (1989), Kulick et al (1994) and Chemloul & Benmedjedi (2010) measured solid fluctuating velocities that decreased with increasing concentration. Their experiments were performed at similar Stokes numbers but at much lower Reynolds numbers (Re = 13 000, 13 800 and 16 200, respectively) and only the data from Chemloul & Benmedjedi (2010) were collected at similar concentrations. Figure 15(b,c) shows that the radial and theta components of the solids velocity fluctuations present no significant influence of the particle concentration at these conditions.…”

A review of turbulence measurement techniques for flotation

“…However, some researchers have also applied the technique to study multiphase flows using LDA or PDA (an extension of LDA). One of these studies involved using a LDA device incorporating an electronic logic system to distinguish signals from water and solid particles in a low solid volumetric concentration (less than 2%) two phase system (solid-liquid suspension) (Sad Chemloul and Benmedjedi, 2010). The beauty of their approach was that electronic logic was employed to speed up the signal processing but unfortunately it was not sufficient to overcome LDA's intrinsic sensitivity to solid concentration.…”