A slug flow model considering the dispersed bubbles entrained from the tail of Taylor bubble(TB) and recoalesced with the successive TB was proposed. Experiment was conducted to test the validity of this model by usin...A slug flow model considering the dispersed bubbles entrained from the tail of Taylor bubble(TB) and recoalesced with the successive TB was proposed. Experiment was conducted to test the validity of this model by using a high-speed camcorder and particle image velocimetry(PIV). It was found that the model was valid for predicting the characteristics of slug flow in airlift pump within average error of 14%. Moreover, large pipe diameter was found to accelerate the rise velocity of TB and decreases void fraction in liquid slug by a small margin.展开更多
Based on the momentum theorem, the fluid governing equation in a lifting pipe is proposed by use of the method combining theoretical analysis with empirical correlations related to the previous research, and the perfo...Based on the momentum theorem, the fluid governing equation in a lifting pipe is proposed by use of the method combining theoretical analysis with empirical correlations related to the previous research, and the performance of an airlift pump can be clearly characterized by the triangular relationship among the volumetric flux of air, water and solid particles, which are obtained respectively by using numerical calculation. The meso-scale river sand is used as tested particles to examine the theoretical model. Results of the model are compared with the data in three-phase flow obtained prior to the development of the present model, by an independent experimental team that used the physical conditions of the present approach. The analytical error can be controlled within 12% for predicting the volumetric flux of water and is smaller than that （±16%） of transporting solid particles in three-phase flow. The experimental results and computations are in good agreement for air-water two-phase flow within a margin of ±8%. Reasonable agreement justifies the use of the present model for engineering design purposes.展开更多
以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位...以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位置的局部平均压力随气体流速的增大逐渐上升达到峰值后减小,峰值随着浸没比的减小而向右移动且上升速度增大;液体流速随着气体流速增大急剧上升达到峰值后几乎保持不变,最大提升效率约为49%,与最大液体流速并不发生在同一个气体流速下;在不同的气流量下,观测到气泡流、帽弹流、弹状流、搅拌流和环状流的出现,不同流型可通过PSD和PDF估计量进行识别;特别是,浸没比越小越有利于形成大气塞。目前,关于气举泵的研究非常有限,本研究结果可为气液固三相流和气液两相流的研究提供数据和技术支撑。展开更多
基金Supported by the National Key Basic Research Development Program of China(2014CB239200)the National Natural Science Foundation of China(51574173,51705372)+1 种基金the Hubei Provincial Natural Science Foundation(2015CFA154)Jiangsu Provincial Natural Science Foundation of China(No.BK20170411)
文摘A slug flow model considering the dispersed bubbles entrained from the tail of Taylor bubble(TB) and recoalesced with the successive TB was proposed. Experiment was conducted to test the validity of this model by using a high-speed camcorder and particle image velocimetry(PIV). It was found that the model was valid for predicting the characteristics of slug flow in airlift pump within average error of 14%. Moreover, large pipe diameter was found to accelerate the rise velocity of TB and decreases void fraction in liquid slug by a small margin.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51374101 and 51474158)the National Basic Research Program of China(973 Program,Grant No.2014CB239203)the Scientific Research Project of Education Department of Hunan Province(Grant No.14B047)
文摘Based on the momentum theorem, the fluid governing equation in a lifting pipe is proposed by use of the method combining theoretical analysis with empirical correlations related to the previous research, and the performance of an airlift pump can be clearly characterized by the triangular relationship among the volumetric flux of air, water and solid particles, which are obtained respectively by using numerical calculation. The meso-scale river sand is used as tested particles to examine the theoretical model. Results of the model are compared with the data in three-phase flow obtained prior to the development of the present model, by an independent experimental team that used the physical conditions of the present approach. The analytical error can be controlled within 12% for predicting the volumetric flux of water and is smaller than that （±16%） of transporting solid particles in three-phase flow. The experimental results and computations are in good agreement for air-water two-phase flow within a margin of ±8%. Reasonable agreement justifies the use of the present model for engineering design purposes.
文摘以空气-水作为介质,探究气举泵气液两相流的压力和流量特性,并基于压力信号的时域、功率谱密度函数(power spectral density,PSD)和概率密度函数(probability density function,PDF)分析鉴别流型。结果表明:除了进气喷嘴附近外,其他位置的局部平均压力随气体流速的增大逐渐上升达到峰值后减小,峰值随着浸没比的减小而向右移动且上升速度增大;液体流速随着气体流速增大急剧上升达到峰值后几乎保持不变,最大提升效率约为49%,与最大液体流速并不发生在同一个气体流速下;在不同的气流量下,观测到气泡流、帽弹流、弹状流、搅拌流和环状流的出现,不同流型可通过PSD和PDF估计量进行识别;特别是,浸没比越小越有利于形成大气塞。目前,关于气举泵的研究非常有限,本研究结果可为气液固三相流和气液两相流的研究提供数据和技术支撑。
