平板表面脊状结构对局部湍流特性的影响研究  

Study on Influence of Riblet Structure of Flat Surface on Local Turbulence Characteristics

作　　者：王松岭[1] 邓宇涵 吴正人[1] 李子骏[1] 郝晓飞[1] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,河北保定071003

出　　处：《华北电力大学学报（自然科学版）》2016年第5期68-74,共7页Journal of North China Electric Power University：Natural Science Edition

基　　金：高等学校博士学科点专项科研基金资助项目(20110036110009);中央高校基本科研业务费专项资金资助项目(2015MS111)

摘　　要：利用Fluent软件,通过脊状平板表面数值模拟,分析黏性阻力、压差阻力、壁面切应力、湍流特性等在脊状平板表面中分布规律,基于能量耗散分析,为脊状结构尺寸选取和局部区域改造提供参考依据。结果表明:脊状尺寸越大越有利于黏性阻力减小,但会导致压差阻力增加,而脊状结构压差阻力主要由迎风面与间隔交接处附近高压区决定。高壁面剪切应力集中于相邻沟槽之间区域前段,且脊状结构越小,光滑表面大于脊状结构内壁面剪切应力的区域也相对越多。对脊状结构平板近壁区涡量与湍流特性分析发现,沟槽最底端部分流体是近乎静止的,脊状结构表面涡量与湍流强度均小于光滑表面,而在脊状结构沟槽内所形成的旋涡区域,能量耗散开始大于光滑表面。This paper analyzes the distribution law of viscous resistance,pressure difference resistance,wall shear stress and turbulence characteristics on the riblet flat surface by using Fluent to make numerical simulation of the riblet flat surface. The energy dissipation is analyzed and references for size selection and local transformation of riblet structure is provided. Results show that a greater riblet structure will lead to smaller viscous resistance and larger pressure difference resistance; however,the pressure difference resistance of riblet structure mainly depends on the windward side and high pressure area near the junction. The biggest wall shear stress lies in the front interval area of the riblet structure,and it is higher than that of a smooth surface model at the same place. Inside the ridge structure,most wall shear stress is lower than that of a smooth surface. The smaller ridge structure will lead to a smaller area where the wall shear stress inside the ridge structure is smaller than that of the smooth surface. By the analysis of vorticity and turbulent characteristics in the near wall region,the paper finds that the fluid in the bottom of the groove is nearly stationary,the surface vorticity and turbulence intensity of the riblet structure are smaller than that of the smooth surface,and in the vortex area within the groove riblet structure,energy dissipation is greater than that of the smooth surface.

关 键 词：脊状结构 数值模拟 分布规律 减阻 优化 

分 类 号：TH4[机械工程—机械制造及自动化] O355[理学—流体力学]