三种形状肋条减阻特性与机理研究

• 作 者: 刘德俊 于洋 王国付 张明明 李雪松
• 机 构: 辽宁石油化工大学石油天然气工程学院,抚顺,113001;辽宁石油化工大学石油天然气工程学院,抚顺113001;中国科学院工程热物理研究所,北京100080;清华大学热能工程系,热科学与动力工程教育部重
• 出 处: 工程热物理学报
• 发表日期: 2016年7期
• 关键词: drag reduction by riblets surface wall shear stress near wall regions of turbule

为了探究不同形状肋条的减阻特性的差异及其机理,本文采用CFD软件对V形肋条、间隔三角形肋条以及刀 刃形肋条三种比较典型的肋条进行数值计算.通过改变肋条的h/s(肋高与肋间距之比)值,选取常见的h/s=0.5和h/s=1两种比值,探索其对肋条减阻的影响规律;从肋条表面切应力、近壁区湍动能等方面分析了上述三种肋条减阻效果差异的原因.研究结果表明t不同形状的肋条的底部都存在大面积的低阻力区,这是肋条能够减阻的共同原因.低阻力区受壁面高度影响,当肋条高度增加,低阻力区摩擦阻力减小.在肋条突出顶部存在高于平板切应力的高阻力区,肋条减阻效果主要决定于该区域的大小.并且,该高阻力区与湍动能密切相关,通过对湍流的分析即可判断不同肋条高阻力区的摩擦强度.“,”In order to explore the mechanism of different shapes of the riblets on drag reducing,this paper uses CFD software of three typical ribs for numerical calculation,such as V shaped ribs,interval-triangular ribs and blade-ribs.By changing the values of h/s(height-to-spacing ratio),selected common values h/s=0.5 and h/s=1,explores the rib drag reduction effects.From the different aspects of wall shear stress,near wall surface turbulent kinetic energy analysis the effects of drag reduction.The results of the study show that:there is a low resistance area of different shapes of the rib bottom,which is the common reason for drag reduction of the ribs.In the prominent top of ribs are higher than that of flat wall shear stress of high resistance area,the effect of reduction depends on the size of that region.And the high resistance area is closely related to the turbulence kinetic energy,by analysis of turbulence could judge the frictional strength of high resistance areas of different ribs.