基于混合RANS/LES方法的空腔流动仿真分析  

Analysis on Cavity Flow Based on Hybrid RANS/LES Method

作　　者：谢露 雷武涛 张昌九 廉佳 赵博文 Xie Lu;Lei Wutao;Zhang Changjiu;Lian Jia;Zhao Bowen(AVIC The First Aircraft Institute,Xi'an 710089,China;Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]航空工业第一飞机设计研究院,陕西西安710089 [2]西北工业大学,陕西西安710072

出　　处：《航空科学技术》2024年第11期41-50,共10页Aeronautical Science & Technology

基　　金：航空科学基金(2019ZA003002)。

摘　　要：飞机在飞行过程中打开起落架舱或武器舱会形成空腔流动,并产生高强度的压力脉动和气动噪声,因此对空腔流动开展研究并分析其非定常流动特点具有重要意义。本文基于混合RANS/LES数值仿真方法,以空腔标模M219为研究对象,进行了空腔非定常流动的研究,并与风洞试验结果进行了对比分析,验证了方法的可靠性,详细研究了搭接网格划分策略,并进行网格敏感性分析,在保证计算精度的同时,提高了计算效率;接着从多个方面对计算得到的非定常流动进行后处理,得到了舱内流场的总声压、频谱特性、瞬时和时均流场结构,为充分理解空腔流动的特点和舱内高强度噪声的产生机理提供了依据;最后,分析了时间步长对空腔流动仿真结果的影响。通过研究,对空腔流动特点进行详细分析,充分验证了混合RANS/LES仿真方法在计算空腔流动特点方面的优越性与实用性,提高了对于混合RANS/LES仿真方法在工程应用中的认识。During the flight,aircraft will generates severe cavity flow when opening the landing-gear bay or weapon bay,causing strong pressure pulsating and Aerodynamic noise.Therefore,it is of great significance to research and analyze the characteristics of unsteady flow.Based on hybrid RANS/LES computational fluid dynamics(CFD)simulation method,the M219 cavity test rig is taken as the research object.The unsteady flow of the cavity is studied and compared with the wind tunnel test results to verify the reliability of the hybrid RANS/LES method.First,patched grids strategy and grid sensitivity are analyzed in detail,so that the efficiency can be improved while ensuring the accuracy of calculation.Then the CFD result of the cavity unsteady flow is processed from different aspects to obtain the overall sound pressure level,the spectrum characteristics,the instantaneous and time-averaged flow structure in the cavity,which provides a basis for fully understanding the flow characteristics of the cavity and the mechanism of the high-intensity noise in the cavity.Finally,the influence of time step on the CFD results of cavity flow is also analyzed,which helps verifing the superiority and practicability of the hybrid RANS/LES simulation method,and improving the knowledge of its engineering applications.

关 键 词：空腔流动 混合RANS/LES方法 搭接网格 网格敏感性 总声压级 频谱特性 POD 

分 类 号：V249[航空宇航科学与技术—飞行器设计]