摘要
为了研究射流撞壁形成液膜的主要特征,采用基于紫外线发光二极管灯-诱导荧光法(UVLEDinduced fluorescence,LEDIF)和高速相机的测试方法对液膜形状和厚度进行了实验研究。结果表明,曲面和平面液膜长度和宽度均随射流速度增加而增加。随着气流速度增加,平面和曲面液膜均长度增加,宽度都减小。随着壁面曲率半径的增加,液膜宽度稍有增加,而液膜长度增加较为明显。随着射流速度的增加,平面和曲面液膜厚度整体上都逐渐减小。而当射流速度进一步增加时,转捩现象开始出现,此时液膜厚度均会迅速增加。曲面液膜的转捩临界速度为19.10~25.08 m/s,而平面液膜转捩速度约为25.08~35.92 m/s。随着气流速度的增加,平面液膜厚度逐渐减小,而曲面液膜厚度在x=0~55 mm时随气流速度增加而增加,在x>55 mm时随气流速度增加而减小。对不同的曲率半径,液膜厚度沿Ψ圆周方向呈“W”形,而随着曲率半径的增加,“W”逐渐变得扁平,但是位于中间(Ψ=0°)的厚度基本不变。
In order to investigate the main characteristics of the liquid film formed by impinging jets on solid walls, the shape and thickness of the liquid film were investigated experimentally based on ultraviolet light emitting diode induced fluorescence(LEDIF)and a high-speed camera. The experiment results showed that the length and width of the liquid films on the curved wall and flat wall increased as the jet velocity increased. As the airflow velocity increased, the lengths of the liquid films on both the flat and curved walls increased, while the widths decreased. The width of the liquid film increased slightly, but the length of the liquid film increased obviously as the radius of curvature increased. The thickness of the liquid film on the flat and curved walls decreased gradually as the jet velocity increased. The transition occurred when the jet velocity reached the critical value, and the thickness of the liquid film increased rapidly. The critical velocity of the liquid film on the curved wall was 19.10—25.08 m/s, while that of the liquid film on the flat wall was 25.08—35.92 m/s, approximately. As the airflow velocity increased, the thickness of the liquid film on the flat wall decreased gradually, while the thickness of the liquid film on the curved wall increased when x=0—55 mm, and decreased when x>55 mm. For the different radius of curvature, the liquid film thickness had a shape of “W” along the circumferential direction Ψ. And the “W”was flattened gradually as the radius of curvature increased, but the thickness in the middle( Ψ=0°) was kept unchanged.
作者
袁韦韦
黄勇
章宏宙
黎露
YUAN Weiwei;HUANG Yong;ZHANG Hongzhou;LI Lu(School of Energy and Power Engineering,Beihang University,Beijing 100191,China;National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics,Beihang University,Beijing 100191,China;Collaborative Innovation Center for Advanced Aero-Engine,Beijing 100191,China)
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2022年第11期2524-2533,共10页
Journal of Aerospace Power
关键词
射流撞击
液膜
液膜形状
液膜厚度
曲面壁
jets impingement
liquid film
liquid film shape
liquid film thickness
curved wall
