摘要
针对横流中单股圆射流冲击模型开展数值研究,在特定的射流雷诺数(1×10^(4))和不同的横流-射流速度比(0.1~0.4)和脉冲频率(20~200 Hz)下,阐释了脉冲激励对射流冲击表面传热特性的影响。研究结果表明:横流中脉冲射流冲击体现出以围巾涡为主体的瞬时涡结构;与稳定射流相比,脉冲射流沿流向偏转程度有显著的减弱,在大的横流-射流速度比下并未形成以肾形涡结构为主导的流动结构,显著提高了冲击靶面的表面传热;脉冲射流与横流的相干过程具有高度的复杂性,导致冲击靶面表面传热与脉冲频率、横流-射流速度比之间存在着复杂的变化关系,在本文的研究参数中,脉冲频率为100 Hz是一个相对较优的脉冲频率。
A numerical study was performed in the present work for a single round-jet impingement in the crossflow,to illustrate the effects of pulsating excitation on flow and heat transfer characteristics of pulsed jet impingement under a fixed jet Reynolds number(1×10^(4))and different crossflow-to-jet velocity ratios(0.1—0.4)and pulsating frequencies(20—200 Hz).The results showed that the scarf-vortex was of the featured vortical structure in the pulsed jet impingement in a crossflow.When compared with the steady jet,the flow deflection of pulsed jet toward the crossflow direction was obviously weakened.Even in a strong crossflow situation,the kidney-vortex-dominated flow structure in the steady jet impingement did not appear in the pulsed jet impingement.Consequently,the convective heat transfer on the target was effectively improved by using pulsed jet impingement in a stronger crossflow.Because of the complexity in the interaction between pulsed jet and crossflow,the convective heat transfer on impinging target was tightly associated with the pulsating frequency and crossflow-to-jet velocity ratio.In the present parameters,a relatively optimal pulsating frequency of 100 Hz was suggested.
作者
王国旺
孙文静
张靖周
谭晓茗
WANG Guowang;SUN Wenjing;ZHANG Jingzhou;TAN Xiaoming(Jiangsu Province Key Laboratory of Aerospace Power System,College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)
出处
《航空动力学报》
北大核心
2025年第2期414-426,共13页
Journal of Aerospace Power
基金
国家自然科学基金(51776097)。
关键词
射流冲击
脉冲射流
横流
表面传热
涡结构
jet impingement
pulsed jet
crossflow
surface heat transfer
vortical structure
作者简介
王国旺(1998−),男,硕士生,主要从事强化传热传质的研究。E-mail:wgw1998@nuaa.edu.cn;通信作者:张靖周(1964−),男,教授,博士,主要从事强化传热计算的研究。E-mail:zhangjz@nuaa.edu.cn。
