基于Spalart-Allmaras-γ-Re_(θt)转捩模型的横流不稳定性转捩预测方法  

Prediction Method of Cross-Flow Instabilities-Induced Transition Based on Spalart-Allmaras-γ-Re_(θt) Transition Model

作　　者：戚琼 韩庆[1] 

机构地区：[1]西北工业大学,陕西西安710072

出　　处：《气体物理》2016年第3期19-24,共6页Physics of Gases

摘　　要：传统的应用稳定性理论对横流不稳定性转捩现象的预测很难与现代CFD并行化计算结合,为了解决这个问题,文章基于SA-γ-—Re_(θt)转捩模型,使用不可压三维边界层相似性解实现横流位移损失厚度Reynolds数在流场中的当地化求解,结合亚音速试验数据-C1准则构建横流不稳定性转捩判据,从而实现了横流不稳定性转捩预测方法的当地化并行求解.首先采用SA-γ-—Re_(θt)转捩模型对NLF(1)-0416翼型进行了流向转捩预测,证实了该模型的正确性.然后应用所建立的横流转捩模型对45°前缘后掠角的NLF(2)-0415无限展长机翼和DLR-F5机翼,以及标准6∶1椭球标模进行了横流不稳定转捩数值模拟,计算结果显示转捩位置均与试验数据吻合较好,证明了文章所建立的方法在不可压边界层转捩预测具有较高的预测精度.The prediction of cross-flow instabilities transition phenomenon is difficult to be combined with modern CFD parallel computation using traditional stability theory. To solve this problem,on the basis of SA-γ-—Re_（θt） transition model,a new transition model was presented in this paper,which solved cross-flow displacement thickness Reynolds number locally using three-dimentional boundary layer similar solution and also set cross-flow instabilities transition criterion referring to C1-criterion. Thereby,it can solve the cross-flow instabilities transition prediction method locally and parallelly. Then,the streamwsie transition of NLF（ 1）-0416 airfoil was predicted to prove the validity of present SA-γ-—Re_（θt）-CF transition model.Adopting this model,numerical simulations of cross-flow instabilities transition were conducted for both infinite swept NLF（ 2）-0415 wing and standard 6∶ 1 prolate spheroid. Computing results show that calculating transition locations are in good agreement with experimental data,which demonstrates the rationality of the model presented.

关 键 词：边界层转捩 转捩模型 湍流模型 边界层相似性解 横流不稳定性转捩 C1准则 

分 类 号：O357.41[理学—流体力学]