基于车身绕流的低雷诺数湍流模型改进研究

强光林; 杨易; 陈阵; 谷正气; 张勇

doi:10.6052/0459-1879-20-095

基于车身绕流的低雷诺数湍流模型改进研究

湖南大学汽车车身先进设计制造国家重点实验室,长沙 410082

基金项目: 1)国家自然科学基金(51975197);国家自然科学基金(51875186);湖南省自然科学基金(2019JJ60063);湖南省自然科学基金(2019JJ60064);湖南省科技创新计划(2017TD2522)

详细信息

通讯作者:
杨易

谷正气

中图分类号: O368
计量
- 文章访问数: 1975
- HTML全文浏览量: 456
- PDF下载量: 155
出版历程
- 收稿日期: 2020-01-10
- 刊出日期: 2020-10-09

RESEARCH ON IMPROVEMENTS OF LRN TURBULENCE MODEL BASED ON FLOW AROUND AUTOMOBILE BODY

State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,Changsha 410082,China

摘要

摘要: 本文将汽车绕流模块化为各典型局部流动,通过常用湍流模型对各典型局部流动进行数值模拟,结果验证了湍流模型对转捩的捕捉能力是准确模拟汽车绕流的关键. 在分析汽车绕流分离及转捩机理的基础上,优化了稳态和瞬态求解方法,改进了湍流模型对转捩的预测能力,进而提高了湍流模型在汽车流场模拟上的精度. 针对汽车绕流的稳态问题,将流线曲率因子及响应阈值引入 LRN $k$-$\varepsilon $ (low Reynolds number $k$-$\varepsilon $) 模型,获得了一种能够更准确预测转捩的改进低雷诺数湍流模型 (modified LRN $k$-$\varepsilon $),改善了原模型对湍流耗散率的过强依赖性及全应力发展预测不足等问题;针对汽车绕流瞬态求解,通过分析 RANS/LES 混合湍流模型的构造思想及特点,引入约束大涡模拟方法,结合本文提出的改进的 LRN $k$-$\varepsilon $ 湍流模型,提出了一种能准确捕捉转捩现象的转捩 LRN CLES 模型. 分别将改进的模型用于某实车外流场和风振噪声仿真中,通过 Ansys Fluent 求解器计算,并将计算结果与常用湍流模型的仿真结果、HD-2 风洞试验结果和实车道路实验结果进行对比,表明改进后的湍流模型能够更准确模拟复杂实车的稳态和瞬态特性,为汽车气动特性的研究提供了可靠理论依据及有效数值解决方法.
- 转捩机理 /
- 低雷诺数湍流模型 /
- RANS/LES 混合湍流模型 /
- 约束大涡模拟
Abstract: The flow around automobiles was modularized into typical local flows in this paper. Through analyzing the characteristics of typical local flows, it is verified that the capture ability of turbulence model to transition is the key to accurately simulate the flow around automobiles. The paper optimized the solutions of steady-state and transient-state problems by analyzing the separation and transition mechanism of the flow, promoted the prediction ability of turbulence model for transition and improved the accuracy of turbulence model for automobile flow field simulation. For the steady-state solution of the flow around automobiles, by introducing the streamline curvature factor and the response threshold into the low Reynolds number (LRN) $k$-$\varepsilon $ model proposed by Jones and Lauder, a modified low Reynolds number turbulence model (modified LRN $k$-$\varepsilon $) which can predict transition more accurately was obtained. This model alleviated the problems of the original model's over-dependence on the turbulent dissipation rate and the insufficient prediction of the total stress development. For the transient-state solution, by analyzing the characteristics of the RNAS(Reynolds-averaged Navier-Stokes equations)/LES(large eddy simulation) mixed turbulence model, introducing the constrained large eddy simulation (CLES) method and the modified LRN $k$-$\varepsilon $ turbulence model proposed in this paper, a transition LRN CLES model that can accurately predict the transition was proposed. These improved models were applied to the simulation of the external flow field and buffeting noise of a real automobile model respectively. Computations were carried out using the ANSYS Fluent solver. The calculation results were compared with the simulation results of the commonly turbulence models, HD-2 wind tunnel test results and real vehicle road test results, it show that the improved turbulence models can more accurately simulate the steady-state and transient-state characteristics of the complex real automobiles, which provides a reliable theoretical basis and effective numerical solution method for the study of automotive aerodynamic.
- transition mechanism /
- low Reynolds number turbulence model /
- RANS/LES mixed turbulence model /
- constrained large- eddy simulation

HTML全文

参考文献(1)

[1]	贾志浩. 基于不同湍流模型的汽车外流场数值模拟. [硕士论文]. 郑州: 郑州大学, 2013: 31-38
[1]	( Jia Zhihao. Numberical simulation of cars in the external flow field based on different turbulence models. [Master Thesis]. Zhengzhou: Zhengzhou University, 2013: 31-38 (Chinese))
[2]	杨中, 杜建一, 徐建中. 基于湍流模型的转捩流动数值计算研究. 工程热物理学报, 2010,31(2):231-234
[2]	( Yang Zhong, Du Jianyi, Xu Jianzhong . Turbulence model based numerical invastigation of transitional flow. Journal of Engineering Thermophysics, 2010, 31(2):231-234 (Chinese))
[3]	Gu ZQ, Chen Z, Feng CJ, et al. Research on the aerodynamic characteristics of the ahmed body with a modified LRN $k$-$\varepsilon$ turbulence model using a transition-code based method. Arabian Journal for Science and Engineering, 2016,41(5):1771-1780
[4]	Wan XW, Yao XM, Wang T. Water drag prediction of amphibious Vehicle based on CFD. Journal of Academy of Armored Force Engineering, 2013,27(3):26-30
[5]	Teramoto S. Large-eddy simulation of transitional boundary layer with impinging shock wave. AIAA Journal, 2005,43(11):2354-2363
[6]	Guilmineau E. Computational study of flow around a simplified car body. Journal of Wind Engineering and Industrial Aerodynamics, 2008,96(6-7):1207-1217
[7]	Zhang J, Gong XZ, Mu JJ. CFD analysis of the turbulence model adopted in distribution process in axial piston pump. Journal of Mechanical Engineering, 2018,54(18):204-211
[8]	Liu LL, Sun ZC, Wan CL. Jet flow field calculation & mechanism analysis on hot-air drying oven based on RNG $k$-$\varepsilon$ model. International Journal of Heat and Technology, 2015,33(1):77-82
[9]	He YB, Gu ZQ, Li WP, et al. Comparison investigation of typical turbulence models for numerical simulation of automobile external flow field. Journal of System Simulation, 2012,24(2):467-472
[10]	Worth NA, Yang ZY. Simulation of an impinging jet in a crossflow using a Reynolds stress transport model. International Journalfor Numerical Methods in Fluids, 2006,52(2):199-211
[11]	Jones WP, Launder BE. The calculation of low-Reynolds-number phenomena with a two-equation model of turbulence. International Journal of Heat & Mass Transfer, 1973,16(6):1119-1130
[12]	Versteeg HK, Malalasekera W. An Introduction to Computational Fluid Dynamics: The Finite Volume Method. New York: Wiley, 1995
[13]	刘俊, 高福平. 近壁面柱体涡激振动的迟滞效应. 力学学报, 2019,51(6):1630-1640
[13]	( Liu Jun, Gao Fuping. Hysteresis in vortex-induced vibrations of a near-wall cylinder. Chinese Journal of Theoretical and Applied Mechanics, 2019,51(6):1630-1640 (in Chinese))
[14]	Zheng X, Liu C, Liu F, et al. Turbulent transition simulation using the $k$-$\omega $ model. International Journal for Numerical Methods in Engineering, 1996,42(10):907-926
[15]	洪正, 叶正寅. 各向同性湍流通过正激波的演化特征研究. 力学学报, 2018,50(6):1356-1367
[15]	( Hong Zheng, Ye Zhengyin. Study on evolution characteristics of isotropic turbulence passing through a normal shock wave. Chinese Journal of Theoretical and Applied Mechanics, 2018,50(6):1356-1367 (in Chinese))
[16]	杜晓庆, 田新新, 马文勇. 圆角化对方柱气动性能影响的流场机理. 力学学报, 2018,50(5):1013-1023
[16]	( Du Xiaoqing, Tian Xinxin, Ma Wenyong. Effects of rounded corner on aerodynamics of square cylinders and its flow mechanisms. Chinese Journal of Theoretical and Applied Mechanics, 2018,50(5):1013-1023 (in Chinese))
[17]	Yang ZY. Numerical study of transition process in a separated boundary layer on a flat plate with two different leading edges. WSEAS Transactions on Applied and Theoretical Mechanics, 2012,7(1):49-58
[18]	Durbin PA. Perspectives on the phenomenology and modeling of boundary layer transition. Flow Turbulence and Combustion, 2017,99(1):1-23
[19]	吴军, 谷正气, 钟志华. SST湍流模型在汽车绕流仿真中的应用. 汽车工程, 2003,25(4):326-329
[19]	( Wu Jun, Gu Zhengqi, Zhong Zhihua. The application of SST turbulence model in the aerodynamic simulation of the automobile. Automotive Engineering, 2003,25(4):326-329 (in Chinese))
[20]	杨小龙, 李铁平. 汽车外流场DES/RANS模拟研究. 湖南大学学报(自然科学版), 2011,38(1):29-34
[20]	( Yang Xiaolong, Li Tieping. DES and RANS of vehicle external flow field. Journal of Hunan University (Natural Sciences), 2011,38(1):29-34 (in Chinese))
[21]	Ashton N, West A, Lardeau S, et al. Assessment of RANS and DES methods for realistic automotive models. Computers & Fluids, 2016,128:1-15
[22]	Franke J, Frank W. Large eddy simulation of the flow past a circular cylinder at $ReD=3900$. Journal of Wind Engineering and Industrial Aerodynamics, 2002,90(10):1191-1206
[23]	Chaouat B, Schiestel, R. Progress in subgrid-scale transport modelling for continuous hybrid non-zonal RANS/LES simulations. International Journal of Heat and Fluid Flow, 2009,30(4):602-616
[24]	Aljure DE, Lehmkuhl O, Rodríguez I, et al. Flow and turbulent structures around simplified car models. Computers & Fluids, 2014,96(96):122-135
[25]	Chen S, Xia Z, Pei S, et al. Reynolds-stress constrained large-eddy simulation of wall-bounded turbulent flows. Journal of Fluid Mechanics, 2012,703(1):1-28
[26]	张清林. 汽车模型风洞关键影响因素研究及数据后处理软件开发. [硕士论文]. 长沙: 湖南大学, 2012: 34-65
[26]	( Zhang Qinglin. Study on influence factor of automotive wind tunnel test and development of the data processing software [Master Thesis]. Changsha: Hunan University, 2012: 34-65 (in Chinese))
[27]	Gu ZQ, Huang TM, Chen Z, et al. Large eddy simulation of the flow-field around road vehicle subjected to pitching motion. Journal of Applied Fluid Mechanics, 2016,9(7):2731-2741
[28]	谷正气, 陈阵, 黄泰明. 基于改进LRN $k$-$\varepsilon $ 模型的汽车气动特性研究. 中国机械工程, 2015,26(18):2550-2555
[28]	( Gu Zhengqi, Chen Zhen, Huang Taiming. Research on aerodynamic characteristics of vehicle with an improved LRN $k$-$\varepsilon $ turbulence model. China Mechanical Engineering, 2015,26(18):2550-2555 (in Chinese))
[29]	江财茂. 基于FE-SEA 方法的汽车气动噪声仿真与控制. [硕士论文]. 长沙: 湖南大学, 2016: 32-52
[29]	( Jiang Maocai. Simulation analysis and control of automobile aerodynamic noise based on hybrid FE-SEA method. [Master Thesis]. Changsha: Hunan University, 2016: 32-52 (in Chinese))
[30]	García J, Mu?oz-paniagua J, Jiménez A, et al. Numerical study of the influence of synthetic turbulent inflow conditions on the aerodynamics of a train. Journal of Fluids & Structures, 2015,56(9):134-151

施引文献(7)

期刊类型引用(3)

1.	高铨，邱翔，夏玉显，李家骅，刘宇陆. 基于LBM的壁湍流跨尺度能量传递结构统计. 力学学报. 2021(05): 1257-1267 . 本站查看
2.	王恋舟，吴铁成，郭春雨. 螺旋桨梢涡不稳定性机理与演化模型研究. 力学学报. 2021(08): 2267-2278 . 本站查看
3.	张珍，叶舒然，岳杰顺，王一伟，黄晨光. 基于组合神经网络的雷诺平均湍流模型多次修正方法. 力学学报. 2021(06): 1532-1542 . 本站查看