摘要
螺旋流动较普通管流对固体颗粒具有更大的输送能力,但流动也更为复杂,尤其是在管道弯管处。采用RNG k-ε模型和DPM模型,对流体携带颗粒螺旋流动经过水平90°弯管时的流动特性进行了数值模拟,其中起旋器为短扭带,扭率为6.2、7.4、8.8,水合物颗粒粒径为0.06 mm、颗粒质量流量为10^(-6) kg/s;将模拟结果与实验结果进行了对比验证,并系统分析了速度、湍流强度及水合物颗粒质量浓度的分布情况。结果表明,由于起旋器的作用,速度极大值被分成两个区域,后随螺旋流的衰弱逐渐向管道中心处融合;由于螺旋流与离心力的共同作用,速度极大值区域在弯管中发生偏移,流体湍流强度和掺混程度显著增强;在螺旋流的影响下,水合物颗粒均匀地分散在近壁面处;相比于无起旋器的管道,流体对颗粒有着更强的携带能力,且扭率越小螺旋流携带能力越大,颗粒越不易沉积在管壁上。
Swirl flow has more conveying capacity for solid particles than ordinary pipe flow,but the flow is also more complex,especially at the elbow.RNG k-εmodel and DPM model were used to simulate the flow characteristics of the swirl flow of the fluid carrying particles passing through a horizontal 90°elbow.The rotating device is a short twisted band with twist rates of 6.2,7.4 and 8.8,the hydrate particle size is 0.06 mm and the particle mass flow rate is 10^(-6) kg/s.The simulation results were compared with the experimental results,and the velocity,turbulence intensity and hydrate particle mass concentration distributions were systematically analyzed.The results indicate that the velocity maxima was divided into two regions due to the role of the rotating device,and then gradually merged into a region at the center of the pipe with the weakening of the swirl flow.The velocity maxima region was shifted in the elbow and the turbulence intensity and the mixing degree of the fluid in the swirl flow of the elbow were significantly enhanced due to the combined action of the swirl flow and centrifugal force.Under the influence of the swirl flow,the hydrate particles were uniformly dispersed near the wall.Compared with the pipeline without twisted band,the fluid has stronger carrying capacity for the particles.And also the smaller the twist rate,the greater the carrying capacity of swirl flow,and the more difficult the particles were to deposit on the pipe wall.
作者
李立军
赵书华
丁博洋
饶永超
王树立
LI Li-jun;ZHAO Shu-hua;DING Bo-yang;RAO Yong-chao;WANG Shu-li(School of Petroleum Engineering,Changzhou University,Changzhou 213000,Jiangsu,China)
出处
《天然气化工—C1化学与化工》
CAS
北大核心
2021年第2期81-86,共6页
Natural Gas Chemical Industry
基金
国家自然科学基金(51574045)
江苏省研究生科研创新计划项目(KYCX20_2573)
中国石油科技创新基金项目(2020D-5007-0211)
常州市应用基础研究计划项目(CJ20200085)。
关键词
螺旋流
弯管
水合物颗粒
扭带
数值模拟
swirl flow
elbow
hydrate particle
twisted band
numerical simulation
