Effects of Non-Smooth Surface Dimple Configuration on Vehicle Body Aerodynamic Characteristics
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摘要: 受仿生学非光滑旋成体减阻启发,以SAE(美国机动车工程师协会)标准模型为研究对象,采用CFD(计算流体力学)数值模拟方法,在SAE模型顶部布置不同排布形式和不同排布密度的凹坑单元,研究其对车身气动性能的影响.通过比较各模型的尾流、气流速度、压力场、湍流动能等流场性能指标,分析非光滑表面减阻机理以及造成各模型流场性质差异的原因.计算结果显示:当凹坑型非光滑单元以矩形排布时模型具有最小的气动阻力,且气动阻力随着凹坑密度的增加而减小,减阻率最高达到4.1%.Abstract: According to the idea of bionic non-smooth revolution bodies, the SAE (Society of Automobile Engineers) standard model was selected as the object of study, and the computational fluid dynamics (CFD) method was used to investigate the effects of different non-smooth surface dimple array forms and densities on the aerodynamic performance of vehicle bodies. Through comparison of such flow field performance indicators as wake flow, airflow velocity, pressure field and turbulence kinetic energy between various models, the drag reduction mechanism of the dimpled non-smooth surface and the reasons for the difference of flow field properties between those models were analyzed. The results show that the minimum aerodynamic drag occurs when the dimple units are arranged in a rectangular configuration, and the aerodynamic drag decreases along with the longitudinal dimple distribution density, attaining the highest drag reduction ratio up to 4.1%.
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Key words:
- drag reduction /
- SAE model /
- CFD /
- non-smooth surface
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[1] 张英朝. 汽车空气动力学数值模拟技术[M]. 北京: 北京大学出版社, 2011:43-45.(ZHANG Ying-chao.Numerical Simulation Technology of Automotive Aerodynamics [M]. Beijing: Peking University Press, 2011: 43-45.(in Chinese)) [2] Ren L Q, Han Z W, Tian L M, Li J Q. Characteristics of the non-smooth surface morphology of living creatures and its application in agricultural engineering[J].Design and Nature II,2004,6(1): 275-284. [3] ZHANG De-yuan, LI Yuan-yue, HAN Xin, LI Xiang, CHEN Hua-wei. High-precision bio-replication of synthetic drag reduction shark skin[J].Chinese Science Bulletin,2011,56(9): 938-944. [4] Lee S J, Jang Y G. Control of flow around a NACA 0012 airfoil with a micro-riblet film[J].Journal of Fluids and Structures,2005,20(5): 659-672. [5] 谌可, 王耘, 曹开元, 宋小文. 仿生非光滑汽车表面的减阻分析[J]. 中国机械工程, 2012,23(8): 1001-1006.(CHEN Ke, WANG Yun, CAO Kai-yuan, SONG Xiao-wen. Analysis of aerodynamic drag reduction on automobile by using bionic non-smooth surface[J].China Mechanical Engineering,2012,23(8): 1001-1006.(in Chinese)) [6] 杨易, 伍奕桦, 范光, 徐永康, 聂云. 车身非光滑表面组合布置对气动特性影响分析[J]. 湖南大学学报(自然科学版), 2013,40(11): 40-45.(YANG Yi, WU Yi-hua, FAN Guang, XU Yong-kang, NIE Yun. Analysis of the influence of non-smooth surface combination arrangement on aerodynamic characteristic[J].Journal of Hunan University(Nature Science),2013,40(11): 40-45.(in Chinese)) [7] 张国耕. 车身仿生非光滑表面气动减阻特性研究[D]. 硕士学位论文. 浙江: 浙江大学, 2010.(ZHANG Guo-geng. Mechanism research on aerodynamic drag reduction of vehicle body with bionic non-smooth surface[D]. Master Thesis. Zhejiang: Zhejiang University, 2010.(in Chinese)) [8] 叶辉. 汽车尾部上翘角与离地间隙的CFD研究[D]. 硕士学位论文. 长春: 吉林大学, 2006.(YE Hui. A parametric study on the diffuser and ground clearance of a simplified car model using CFD[D]. Master Thesis. Changchun: Jilin University, 2006.(in Chinese)) [9] 董立伟, 谷正气, 刘水长, 王宁. 网格划分对汽车外流场数值计算影响的研究[J]. 汽车科技, 2012(1): 12-15.(DONG Li-wei, GU Zheng-qi, LIU Shui-chang, WANG Ning. Effect of meshing on numerical simulation of external flow field around vehicle[J].Auto Mobile Science & Technology,2012(1): 12-15.(in Chinese)) [10] 涂尚荣, 张扬军, 谢今明, 杨胜, 郑孟伟. 汽车外部流场仿真的复杂网格系统生成[J]. 汽车工程, 2012,24(5): 408-411.(TU Shang-rong, ZHANG Yang-jun, XIE Jin-ming, YANG Sheng, ZHENG Meng-wei. Grid generation for CFD simulation of vehicle aerodynamics[J].Automotive Engineering,2012,24(5): 408-411.(in Chinese)) [11] 赵继妮. 仿生非光滑表面旋成体减阻性能分析[D]. 硕士学位论文. 长春: 吉林大学, 2005.(ZHAO Ji-ni. Analysis of drag reduction on revolution bodies with bionic non-smooth surface[D]. Master Thesis. Changchun: Jilin University, 2005.(in Chinese)) [12] 赵军. 凹坑形仿生非光滑表面的减阻性能研究[D]. 硕士学位论文. 大连: 大连理工大学, 2008.(ZHAO Jun. Study of drag reduction of the dimple bionic non-smooth surface[D]. Master Thesis. Dalian: Dalian University of Technology, 2008.(in Chinese)) [13] SONG Xiao-wen, ZHANG Guo-geng, WANG Yun, HU Shu-gen. Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels[J].Journal of Zhejiang University-Science A (Applied Physics & Engineering),2011,12(7): 543-551.
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