压缩性修正对γ-Re_θ转捩模型的影响研究  

Effects of compressibility correction on γ-Re_θ transition model

作　　者：夏陈超 姜婷婷[1] 郭中州 陈伟芳[1] 

机构地区：[1]浙江大学航空航天学院,浙江杭州310027

出　　处：《空气动力学学报》2015年第5期603-609,共7页Acta Aerodynamica Sinica

基　　金：国家重点基础研究发展计划(2014CB340201)

摘　　要：将基于流场当地变量的γ-Reθ转捩模型加入可压缩RANS方程计算程序,对平均流场控制方程、湍流和转捩控制方程进行基于LU-SGS的隐式紧耦合求解。结合三种压缩性修正方法对高超声速平板、双楔和圆锥流动进行了数值模拟,给出了壁面斯坦顿数、热流值和实验值的比较,以及湍动能和间歇因子分布云图。数值计算结果表明,相同来流湍流度下不同压缩性修正方法得到的转捩位置差别较大。相比于未修正的模型,基于当地马赫数压缩性修正后的转捩位置最靠后,其对带有分离的双楔流动预测较为准确;基于来流马赫数的压缩性修正仅使得转捩位置稍有延迟;对湍动能源项的压缩性修正可提高模型在转捩后湍流段的热流预测精度。Boundary layer transition plays a significant role in the prediction of aerodynamic and aerothermodynamics characteristics of hypersonic vehicle.The commonly used correlation based onγ-Reθ transition model is implemented into a Reynolds-Averaged Navier-Stokes solver in order to evaluate its capability in hypersonic flows.The mean flow and turbulent flow equations are solved simultaneously based on the LU-SGS method.Three compressibility correction meth-ods are adopted to simulate the hypersonic flows around a flat plate,a double wedge and a cone body.Results of Stanton number,heat flux on walls,contours of turbulence kinetic energy and intermittency factor are presented.The results ofγ-Reθ transition model show better flow essen-tial than that of full laminar or full turbulent results.The transition onset positions obtained by different compressibility methods under the same free stream turbulence intensity varied signifi-cantly.Compressibility correction based on local Mach number delays the transition onset great-ly,while the correction of source term of turbulent kinetic energy equation improves the accuracy of heat flux on turbulent section of the wall.Rational selection of compressibility correction method should rely on the type of flow.Elaborate and reliable compressibility correction method still need to be further investigated.

关 键 词：高超声速 RANS方程 γ-Reθ转捩模型 紧耦合 压缩性修正 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]