Theoretical approach on the turbulence intensity of the carrier fluid in dilute two-phase flows

Numerical study of bubbly upflows in a vertical channel using the Euler–Lagrange two-way model

“…Large bubbles (their diameter is approximately larger than 1.5 mm) enhance the liquid-phase turbulence, whereas small bubbles reduce the liquid turbulence. This point is also accepted by Kim et al (2005). They pointed out that when there is no change in volume of the dispersed flows which include bubbly flow, droplet flow, and particle-laden flow, the production and dissipation of the turbulent continuous phase can be understood by similar mechanisms.…”

“…When the bubble deformation is neglected in computations, bubbles effects on the Reynolds stress is similar to that of particles (Kim et al, 2005). Bubbles effects on the Reynolds stress may be caused by changes in the magnitude velocity fluctuations and/or through the quadrant distribution of u 0 v 0 (Pan and Banerjee, 1997).…”

Turbulence Modulation by Small Bubbles in the Vertical Upward Channel Flow

“…Kato et al deduced that the bubble influencing the liquid turbulence is just like the influence of the solid particle on the gas turbulence: large bubbles enhance the liquidphase turbulence, whereas small bubbles reduce the liquid turbulence [5]. This view is also accepted by Kim et al [6], and they pointed out that when there is no change in volume of the dispersed phase, the turbulence production and dissipation can be understood by similar mechanisms. So et al [7] and Molin et al [8] considered that the lift force direction and magnitude are sensitive to the bubble size, so it is possible that the reason for the suppressed velocity fluctuations is the modification of the global flow structure caused by the bubble accumulation near the wall.…”

Effect of particle clusters on turbulence modulations in liquid flow laden with fine solid particles

“…Kim et al (2005) considered that, when there is no change in the volume of the dispersed flows, which include the bubbly flow, the droplet flow, and the particle-laden flow, the turbulent production and dissipation of the continuous phase can be understood by similar mechanisms. Some judgement standards of the turbulent modulation by the particles are summarized in Table 2.…”