Heat Transfer in Aerated Tower Filled with Non-Newtonian Liquid

Abstract

Correlations of heat transfer coefficients from a jacket wall or an immersed cooling coil were obtained for the aerated tower including physical properties of the liquid, viscosity correction term, liquid superficial velocity, and gas superficial velocity. It was also determined that heat transfer coefficients for non-Newtonian liquids could be correlated by the same correlative equations for Newtonian liquids using the apparent viscosity calculated from the flow curve and the local average shear rate defined in this study. As the local average shear rate at the wall surface was much larger than that near the cooling coil, it was more efficient to use a cooling coil for thermal control of the aerated tower.

Concentric‐tube airlift reactors: Effects of geometrical design on performance

“…Neither liquid velocity nor the gas holdup is considered, since these are not independent variables, and they are not usually known apriori. The gas density was considered negligible, compared with the density of the liquid, and the effective viscosity was based on the relation proposed by Nishikawa et al (1977) where K and n are the consistency and flow behavior indexes, given in Table 2. The disengagement ratio defined by Siege1 and Merchuk (1991):…”

Heat‐transfer characteristics in viscous gas‐liquid and gas‐liquid‐solid systems

“…18 obtained primarily from a mechanistic viewpoint has also been reported by several researchers based on their correlation of experimental data. For example, Nishikawa et al (1977) obtained a relationship of the form hava U;l6' in the bubble column based on his experimental data for viscous liquids under moderate gas velocities. For three-phase fluidized beds, using Eqs.…”

Effect of scale-up on average shear rates for aerated non-Newtonian liquids in external loop airlift reactors

“…Nishikawa et al (1977) used the heat transfer coefficient from an immersed cooling coil and a jacketed wall in a bubble column as the measurable parameter. The effective shear rate was calculated as a function of superficial gas velocity by:…”