三维荧光油流技术的试验研究

Experimental investigations of 3D luminescent oil flow techniques

荧光油流摩擦力场测量技术可以得到模型表面的全局摩擦力信息。该技术基于传统荧光油流技术发展而来,运用荧光油流技术作为原始数据获取手段,对试验图像运用HS光学流动算法进行图像处理得到模型表面油膜厚度随时间轴的变化量,依据动量定理对油膜厚度变化量进行计算得到当地的相对摩擦力信息实现表面摩擦力的可视化测量。本文运用该技术在低速风洞中对平板模型、75°平板三角翼、平板-翼型角区三维模型的表面摩擦力场分布情况进行测量,得到各模型表面的相对摩擦力分布和摩擦力线,并与平板模型Blasius层流解和三角翼模型经典流场结构进行对比。试验结果表明:在低速环境下该测量技术可以应用于模型表面摩擦力的可视化测量,所得摩擦力分布及表面流动情况基本可靠。

Luminescent oil flow technique is a way of measuring global skin friction.This technique is developed on the basis of traditional luminescent oil flow method.It is a visible measurement technique extracting original experiments data by using traditional luminescent oil flow.These data are further processed by HS optical flow algorithm to obtain the surface model of oil film thickness variation on temporal axis.The thickness variation indicates the local relative surface skin friction according to the momentum theorem.In this paper,we used this measurement technique to diagnose the skin friction distributions of a flat plate,a 75°delta wing and a junction model in low speed wind tunnel.The distributions of relative friction and the friction line were also achieved.A comparison was shown between the plate model Blasius laminar flow solutions and classic flow structure of the delta wing model.The test results indicate that this visible skin friction measurement method can be used to provide skin friction information conveniently and uniquely in low speed wind tunnel experiments.