Chemical Engineering Science, Vol.176, 220-232, 2018
Hydrodynamics and flow mechanism of foam column Trays: Contact angle effect
Wettability has significant influence on fluid flow inside foam ceramics. Foam SiC valves with various wettability were prepared by a facial bottom-up strategy. Subsequently, pressure drop, weeping and gas distribution were studied. Results indicate that pressure drop decreases remarkably with increasing contact angle (CA), 43% at most; weeping rate presents a peak at CA<90 degrees but monotonous decrease at CA>90 degrees; gas distribution becomes more uniform with increasing CA at small F-factor but presents obvious boundary effect at large F-factor. To illustrate the CA effect, we propose a new strategy for pressure drop decomposition, introducing the fourth part called CA-induced pressure drop by modifying classical three-component strategy, which also catalyzes a new pressure drop measuring strategy. In the meanwhile, the mathematical model to predict pressure drop is proposed and shows good agreement with experiments. Moreover, process model to illustrate the mechanism is proposed based on interfacial phenomena, force analysis and flow patterns. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:Distillation;Foam ceramics;Wettability;Pressure drop;Gas distribution;Interfacial phenomena