Experimental study and theoretical model described transition regime parameters and hydrodynamic parameters in a gas-liquid dispersion column

الملخص EN

Experimental study of total gas hold-up, bubble diameters and rise velocity of the swarm of bubbles, and regime transition point in dispersion column.

The experimental runs were carried out in two perspex columns of 7.5 cm and 15 cm inside diameter.

The present work investigated the effect of two system of two-liquid phase (air-water, and air-aqueous-n-propanol solution) in the range (0.05-0.7Wt%), superficial air velocity in the range (0.025-0.3 cm/s) and two air distributor plates of 1.5 mm diameter holes (i.d.= 7.5 cm, holes=36 and free area=1.4%, and i.d.= 15 cm holes=121 and free area=1.2%).

In this paper, a Krishna et al., 1999 model has been improved, and the combination of this improved model with derived drift flux model have been described the hydrodynamics of dispersion column operating in homogeneous and heterogeneous flow regimes (i.e.

transition regime parameterest rans and Utrans ).

Photographic technique was used by taking three pictures in different view (different angle) of the dispersion column, to measure the hydrodynamic parameters.

From the experimental data, it was found that the addition of a small amount of npentanol to distilled water and varying dispersion column diameter, is the main factor that affects, the transition flow regime.

Also the experimental results show that the values of total gas hold-up for air-aqueous n-pentanol solution system are greater than the values for air-water system, but the values of total gas hold-up decrease with dispersion column diameter for two systems.

The experimental data show that the values of total gas hold-up and superficial air velocity at transition regime varied with the weight percent of n-pentanol by fitting of second order polynomial regressions for the two dispersion column diameters