Some flow characteristics of a vertical liquid jet system having downcomers

Characterization of gas-liquid parameters in a down-flow jet loop bubble column

“…Higher gas-liquid contact can be obtained by increasing bubble penetration, but it requires enough downward liquid flow to overcome the buoyant force of the bubbles produced by the liquid jet. In another way, a higher residence time of the entrained bubbles can be obtained by plunging a vertical liquid jet in a vertical column (Ohkawa et al, 1986;Bando et al, 1988;Yamagiwa et al, 1990). Milenković et al (2007) reported the characteristics of large coherent structures in turbulent, periodically-excited, as well as naturallydeveloping bubbly jets and the interactions between bubbles and large-scale vortices.…”

Experimental and Theoretical Study of the Characteristics of Submerged Horizontal Gas Jets and Vertical Plunging Water Jets in Water Ambient

“…The values of c 1 , c 2 , c 3 , and c 4 were found to be 10.5, 0.54, -0.56, and 1.39, respectively, for two inclined plunging jets and 5.5, 0.73, -0.26, and 1.11 respectively for one inclined plunging jet by given Ohkawa et al (1986). Ohkawa et al, (1987) studied the vertical water jets and suggested for the dimensionless bubble penetration depth, H p /d N , the following expression:…”

“…In addition, he studied the effect of nozzle design on the entrainment ratio for different types of nozzle diameter. Ohkawa et al (1986) . An empirical correlation was suggested to predict the entrainment ratio over the range of conditions tested as the following on:…”

“…Also, depends on the physical properties of the fluid (mainly viscosity and surface tension), σ, the design of the jet nozzle (e.g. the nozzle diameter, d N and nozzle length, l N ), the jet angle (α), the length of the free-falling jet, x 1 , and the jet turbulence, T u , (Bin 1993, Chanson et al 2004, Cummings and Chanson 1997, Kusabiraki et al, 1990, Ohkawa et al 1986). …”

“…These two patterns occur simultaneously for an intermediate distance. Furthermore, the nozzle length to diameter (l N /d N ) ratio is an important factor in nozzle design (Bin, 1993;Burgess and Molloy, 1973;Ohkawa et al, 1986;Vandesande and Smith, 1976). For practical reasons, Ohkawa et al (1986) recommended the use of a relatively small l N /d N ratio (much smaller than 50).…”