为了考察肋条结构对管道减阻效果的影响,利用自行设计的管道流动试验平台和PIV测试系统,通过对比平板表面,研究了3种尺寸的V型肋条结构表面对管道压降和流场流动特性的影响.试验结果表明:肋条具有减阻效果,减阻率与归一化肋高h+及雷诺数Re有关;当归一化肋高4＜h+＜15,3种肋条都具有减阻效果;高度为0.5 mm的肋条减阻效果最好,其最大减阻值约为1 1.91％.利用PIV测试系统对肋条结构减阻原因进行的研究表明:对比光滑结构,肋条结构的存在使得边界层增厚,流向与法向均方根速度减小,流向与法向速度脉动减弱且雷诺应力减小,边界层流动更加稳定,从而可达到减阻的目的.%In order to study the influence of the rib structure on pipeline drag reduction effect,using the self-designed pipeline flow experiment platform and the PIV testing system,and through comparing plate surfaces,the influence of V-shaped rib structure surfaces with 3 sizes on pipeline pressure drop and flow field flow characteristic is studied.The experiment results show that the rib has drag reduction effect,and the drag reduction rate is related to the uniformization rib height h+ and Reynolds number Re;ifthe uniformization rib height is 4 ＜ h+ ＜ 15,the three kinds of ribs all have drag reduction effect;the rib with 0.5 mm height has the best effect,which highest drag reduction value is about 11.91％.The PIV testing system is used to study the drag reduction reasons ofthe rib structure,and the study shows that compared with the smooth structure,the rib structure can increase the bounding layer thickness,reduce the flow direction and normal root mean square speed,weaken the flow direction and normal speed impulse,decrease the Reynolds shear stress and stabilize the bounding layer flow,which can realize the purpose of drag reduction.
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