变异卵圆形凹坑非光滑表面的气动摩擦减阻研究（英文）

发布时间：2018-03-17 00:23

本文选题：变异卵圆形凹坑　切入点：非光滑表面　出处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2017年01期 　论文类型：期刊论文

【摘要】：目的:仿生非光滑表面具有降低表面摩擦阻力的作用,传统的非光滑结构有沟槽和凹坑等。本文旨在研究变异卵圆形凹坑非光滑表面的气动摩擦减阻特性及其减阻机理。创新点:1.以仿生学理论为基础,提出变异卵圆形凹坑结构模型,突破现有非光滑结构类型的局限;2.采用参数构造的方法研究变异卵圆形各构造参数对表面摩擦阻力减阻的影响。方法:1.采用半径、半轴和坑深3个尺寸参数对变异卵圆凹坑结构进行几何定义,并将非光滑结构以一定纵向间距按矩形排布布置在仿真模型底部;2.以3个尺寸参数和纵向间距设计"三水平四因素"正交实验,在不同气流流速下进行数值模拟仿真;3.通过速度矢量、边界层厚度变化和压力分布研究变异卵圆形凹坑非光滑表面的气动摩擦减阻机理。结论:1.变异卵圆形非光滑表面具有一定的气动摩擦减阻效果,和光滑表面相比,在空气来流速度为24 m/s时,有10%的减阻效果;2.正交实验分析表明,4个试验因素对减阻效果的影响从大到小排列分别为:半径、坑深、半轴和纵向间距;3.变异卵圆形凹坑表面增加了边界层的厚度,降低了近壁面区域的速度梯度,减少了剪切力,从而起到了减少摩擦阻力的效果。
[Abstract]:Objective: the bionic non-smooth surface can reduce the friction resistance of the surface. Traditional non-smooth structures include grooves and pits. This paper aims to study the drag reduction characteristics and drag reduction mechanism of non-smooth surface of variable oval pits. A model of variable oval concave structure is put forward to break through the limitation of existing non-smooth structure types. 2. The influence of structural parameters of variable oval structure on friction drag reduction of surface is studied by parameter structure method. The geometric definition of the variable oval concave structure is given by three dimensional parameters of the semi-axis and the pit depth. At the bottom of the simulation model, the non-smooth structure is arranged at the bottom of the simulation model with a certain longitudinal spacing according to the rectangular spacing. The orthogonal experiment of "three water and four factors" is designed with three dimension parameters and longitudinal spacing. Numerical simulation is carried out under different airflow velocity. The variation of boundary layer thickness and pressure distribution study the drag reduction mechanism of non-smooth surface of variable oval pit by aerodynamic friction. Conclusion: 1. Variation oval non-smooth surface has a certain aerodynamic friction drag reduction effect compared with smooth surface. When the air flow velocity is 24 m / s, the drag reduction effect is 10%. The orthogonal experimental analysis shows that the influence of the four test factors on the drag reduction effect is arranged from large to small as follows: radius, pit depth, The surface of the variant oval pit increases the thickness of the boundary layer, decreases the velocity gradient near the wall and reduces the shear force, thus reducing the friction resistance.
【作者单位】： State
【基金】：Project supported by the National Natural Science Foundation of China(No.51375439)
【分类号】：O313.5

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