基于转捩模型及声比拟方法的高精度圆柱分离涡/涡致噪声模拟  

High-order delay detached-eddy simulations of cylindrical separated vortex/vortex induced noise based on transition model and acoustic analogy

作　　者：王光学[1,2] 王圣业 葛明明 邓小刚[1] Wang Guang-Xue;Wang Sheng-Ye;Ge Ming-Ming;Deng Xiao-Gang(College of Aerospace Science and Engineering,National University of Defense Technology Changsha 410073,China;School of Physics,Sun Yat-sen University,Guangzhou 510275,China)

机构地区：[1]国防科技大学空天科学学院,长沙410073 [2]中山大学物理学院,广州510275

出　　处：《物理学报》2018年第19期170-180,共11页Acta Physica Sinica

基　　金：国防科学技术大学科研计划(批准号:ZDYYJCYJ20140101)资助的课题~~

摘　　要：基于七阶加权紧致非线性格式(WCNS-E8T7),结合延迟分离涡模拟(DDES)和Ffowcs WilliamsHawkings声比拟方法,对亚临界雷诺数下单圆柱、圆柱-翼型的分离涡/涡致噪声问题进行了数值模拟.针对亚临界雷诺数下圆柱尾迹中的转捩问题,发展了基于γ-Reθ模型高精度转捩-延迟分离涡模拟(Tran-DDES)方法,并与传统基于全湍流剪切应力输运(SST)模型的高精度DDES方法进行了对比.单圆柱模拟结果表明:传统SST-DDES方法会造成平均流场的回流区增大,压差阻力偏小等问题;而添加转捩模型的Tran-DDES方法与实验符合得很好.圆柱尾迹中添加翼型后,翼型对圆柱附近流场产生影响,使SST-DDES方法造成的圆柱后回流区偏大的问题减弱,并与Tran-DDES模拟结果差异变小.但在脉动量预测以及脉动产生的噪声预测方面, Tran-DDES方法仍与实验符合得更好.The numerical prediction of transition from laminar to turbulent flow has proven to be an arduous challenge to computational fluid dynamics（CFD）. Few approaches can provide routine accurate results within the cost limitations of engineering applications. In the present paper described is the application of a γ-Reθ transition model in combination with the delay detached eddy simulation（DDES） and Ffowcs Williams and Hawkings（FW-H） acoustic analogy method to cylinder vortex/vortex induced noise at a subcritical Reynolds number. In the process of numerical simulation,a traditional DDES based on the full-turbulence model SST is carried out for comparison and a 7th-order weighted compact nonlinear scheme（WCNS-E8T7） is adopted to ensure that the physical models are not affected by numerical dissipation or dispersion. In the first case, single cylinder cross-flow at ReD = 4.3 × 10~4 and Ma = 0.21, is considered as a benchmarking problem for validating turbulence models and aerodynamic noise prediction methods. Its aerodynamic coefficients, St, CL and CD at root-mean-square（rms） and averaged values are measured by Szepessy and Bearman,while an acoustic measurement was recently made at Ecole Centrale de Lyon. The traditional DDES only based on SST model（SST-DDES） delays the instability of the shear layer on the sides of the cylinder, which leads to the recirculation zone in mean flow to grow and the induced drag to increase. Moreover, the vortex shedding frequency predicted by SST-DDES is larger than the actual value, which makes the whole sound pressure level（SPL） spectrum move toward high frequency region. However, combining the γ-Reθ transition model, the DDES（called Tran-DDES in the present article） can give the results in good agreement with the experimental data. In the second case considered is an airfoil in the wake of the cylinder. The flow condition is similar to that in the first case and the experimental results are also obtained at Ecole Centrale de Lyon. The issue of SST-D

关 键 词：转捩模型 气动声学 分离涡模拟 加权紧致非线性格式 

分 类 号：O357.5[理学—流体力学]