Effect of fiber length distribution on gas holdup in a cocurrent air–water–fiber bubble column

An experimental investigation is reported on the effect of fiber length distribution on gas holdup in a cocurrent air–water–fiber bubble column. Different combinations of 1 and 3 mm Rayon fibers are used to simulate different fiber length distributions. At a constant total fiber mass fraction, gas holdup generally decreases with increasing mass fraction of the 3 mm Rayon fiber while other conditions remain constant. Crowding factors estimated using four different methods (Nc=Nc,ANc=Nc,A, Nc*, Nc,LNc,L, and Nc,MNc,M) and the parameters Nc,LNf0.20.8 and Nc,MNf0.20.8 are tested on their performance to quantify the overall effects of fiber mass fraction and fiber length and its distribution on gas holdup. Nc,LNf0.20.8 and Nc,MNf0.20.8 provide the best characterization of the fiber effects on gas holdup in the cocurrent air–water–fiber bubble column. The crowding factor estimated using the model-based average fiber length (Nc,M)(Nc,M) also provides a good characterization and is better than the other crowding factor definitions.