多孔碳毡内气相析出诱导的气液两相流动特性研究  

Investigation of gas-liquid two-phase flow induced by gas evolution in carbon felts

作　　者：单天祥 叶强[1] 

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《水动力学研究与进展（A辑）》2017年第6期719-724,共6页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金(51276111)~~

摘　　要：碳毡是一种高孔隙率的纤维堆积多孔材料,被广泛应用于化工、能源等领域。液体流经碳毡时,其中的溶解气会在升温或降压等因素的作用下过饱和析出,从而影响液相的流动。该文以溶解有饱和空气的液态水为工质,利用加热诱导析气的方法实现了对这种特殊气液两相流的可视化观测,并借助测压法和称重法实现了碳毡内流动阻力和空泡份额的定量测量。结果表明:过饱和析出的气泡在碳毡内有明显的滞留效应,导致液相流动阻力与空泡份额的显著增加;流速的提高增强了流体对滞留气泡的冲刷,从而降低了气相含量及其对液相流动的阻碍。Carbon felt is a kind of fibrous packing porous medium with high porosities, which has been widely employed in the fields of chemical and energy engineering. As liquid flows through carbon felt, dissolved gas might evolve because of heating or depressurization, and thus affects liquid flow. This peculiar gas-liquid two-phase flow is visualized in the experiment which is realized by pumping air-saturated liquid through heated carbon felt. The flow resistance and the void fraction are quantified by pressure measurement and weighing method respectively. It is found that apparent amount of evolved gas bubbles tends to reside in the felt leading to significant increases in both flow resistance and void fraction. In addition, the increases of liquid velocity enhance the sweeping of entrapped gas bubbles, which result in decreased void fractions and lower resistance of liquid flow.

关 键 词：碳毡 气相析出 渗透率 空泡份额 气液两相流动 

分 类 号：O359.1[理学—流体力学]