翅片法向振动对流动和传热影响的仿真研究  

Simulation study on influence of normal vibration of fins on flow and heat transfer

作　　者：周尧[1] 汪杨 赵亮[1] 文雯[1] 杨雨薇 王滨 ZHOU Yao;WANG Yang;ZHAO Liang;WEN Wen;YANG Yuwei;WANG Bin(China Aeronautical Computing Technique Research Institute,Xi'an 710119)

机构地区：[1]西安航空计算技术研究所,陕西西安710119

出　　处：《机械设计》2023年第7期109-114,共6页Journal of Machine Design

基　　金：国家科技重大专项(2017-V-0014-0066)。

摘　　要：散热对于航空电子设备十分重要,为了利用飞机振动提高航空电子散热能力,以及为航空电子设备的热设计提供参考,在计算流体力学软件中建立了平直翅片在流场中法向振动的仿真模型,并分析了振幅、振动频率和雷诺数对换热和流场流动特性的影响。结果表明:翅片在流场中的法向振动能够起到强化换热作用,随着振幅的增大或频率的提高,强化换热的效果更加明显。在文中研究的范围内,定义的换热强化率最高达229%。翅片振动可以在流体中形成多个由边界层处汇入主流的气团,加强了壁面附近热空气与主流的低温空气混合,因而增强了壁面与流体的热交换。强化换热效果是在来流的冷空气输运和振动引起的流体混合综合作用下获得的,当来流速度不断提高,输运作用逐渐占据主导时,流体混合作用相对变小,使换热强化率降低。Heat dissipation is very important for avionics.In this article,in order to use aircraft's vibration to improve heat dissipation of avionics and provide reference for the thermal design,the simulation model of the flat fins with normal vibration in the flow field is set up by means of the CFD software;the influence of amplitude,vibration frequency and Reynolds number on heat transfer and the flow field characteristics is analyzed.The results show that,the normal vibration of the fins in the flow field enhances heat transfer,and the effect of heat transfer enhancement becomes more obvious with the ever-growing amplitude or frequency.Within the scope of this study,the defined rate of heat transfer enhancement is up to 229%.Thansks to the fin vibration,air masses that go into the mainstream from the boundary layer take shape,which will promote the mix of hot air near the wall with the mainstream cold air,thus resutling in strengthened heat exchange between the wall and the air.The effect of heat-transfer enhancement is obtained with a combination of the cold-air transport and the fluid mix caused by vibration.When the inflow velocity increases,the cold-air transport gradually dominates,and the fluid mix becomes weak;as a result,the rate of heat-transfer enhancement decreases.

关 键 词：平直翅片 法向振动 数值模拟 强化换热 流动特性 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]