Effect of Gas Distributor on Gas Holdup in Fiber Suspensions

Date
2004-07-01
Authors
Su, Xufeng
Heindel, Theodore
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Research Projects
Organizational Units
Mechanical Engineering
Organizational Unit
Journal Issue
Series
Abstract

Two different aeration plates are used to study their effect on gas holdup and flow regime transition in fiber suspensions. Two gas distributors with different open areas (A = 0.57% and 2.14%) and the same orifice diameter (do = 1 mm) are used, and experiments are performed using three different Rayon fiber lengths (L = 3, 6, and 12 mm) over a range of superficial gas velocities (Ug ≤ 18 cm/s) and a range of fiber mass fractions (0 ≤ C ≤ 1.8%) in a 15.24 cm diameter semi-batch bubble column. Experimental results show that the distributor with A = 2.14% tends to produce lower gas holdup than the one with A = 0.57% for both air-water systems and fiber slurries. However, the effect of distributor open area on gas holdup diminishes at high fiber mass fractions (C ≤ 1.2%). Both distributors generate homogeneous, transitional, and heterogeneous flow regimes over the range of superficial gas velocities for air-water and low fiber mass fraction suspensions. However, the distributor with A = 2.14% enhances the flow regime transition, i.e., the superficial gas velocity at which the transitional flow regime appears is lower. Additionally, the fiber mass fraction at which purely heterogeneous flow is observed is lower when A = 2.14%.

Description

This is a conference proceeding from ASME 2004 Heat Transfer/Fluids Engineering Summer Conference 3 (2004): 507, doi:10.1115/HT-FED2004-56222. Posted with permission.

Keywords
bubble column, drift flux, gas holdup, gas distributor, fiber suspension, flow regime
Citation
DOI