仿生肋条减阻技术在输气管道中的应用

摘要

近年来,随着天然气需求量的不断增加,输气管道输送效率问题越来越受到重视.由于输气管道的主要损失为摩擦阻力损失,因此降低摩擦阻力成为研究输气管道的重点.为探究V形肋条在输气管道减阻中的应用,采用FLUENT软件对两种不同几何尺寸的V形肋条进行数值模拟,把大管径管道仿生肋条的减阻研究近似转换为平板输气管道的数值模拟.研究结果表明,V形肋条输气管道与光滑输气管道在对数层的速度-位置轮廓线不同;在相同天然气进口速度下,V形肋条肋顶的切应力大于肋底的切应力,且肋底的近壁局部湍动能较小;肋高h、肋宽s均为0.90 mm的V形肋条输气管道的减阻效果好于肋高h、肋宽s均为0.51mm的V形肋条输气管道.%In recent years, with the increasing demand for natural gas, more and more attention was paid to the transmission efficiency of gas transmission pipeline.Because the main loss of gas pipeline was the friction resistance, therefore reducing the resistance became the focus of the study.To explore the V-shaped riblets in transmission gas pipeline of drag reduction application, FLUENT was used to simulate two different geometric size of V-shaped riblets.The pipeline drag reduction of bionic riblets could approximate switch into flat gas transmission for numerical simulation.The results of the study showed that: compared with the smooth gas transmission pipeline, V-shaped riblet gas transmission pipeline of the turbulent boundary layer of velocity profile in the logarithmic layer was different;in the same gas velocity inlet, V-shaped riblet at the top of the shear stress was greater than the bottom of the riblet, also riblet on the bottom of the near wall local turbulent kinetic energy was small;the riblet height and spacing size of both 0.90 mm V-shaped riblet pipeline had more drag reduction effect than the size of both 0.51 mm V-shaped riblet pipeline.