汽车风窗玻璃外流场特性及其对雨滴运动影响的研究  

A Study on the External Flow Field Characteristics of Vehicle Windshield and Their Effects on Rain Droplet Motion

作　　者：姜立标[1,2] 丘华川 Jiang Libiao;Qiu Huachuan(Jilin University,State Key Laboratory of Automotive Simulation and Control,Changchun 130025;School of Mechanical&Automotive Engineering,South China University of Technology,Guangzhou 510640)

机构地区：[1]吉林大学,汽车仿真与控制国家重点实验室,长春130025 [2]华南理工大学机械与汽车工程学院,广州510640

出　　处：《汽车工程》2018年第10期1230-1238,共9页Automotive Engineering

基　　金：国家自然科学基金(51275175)；汽车仿真与控制国家重点实验室开放基金资助。

摘　　要：本文中对风窗玻璃的外流场特性进行数值仿真,以揭示其对雨滴运动的影响。首先,采用标准k-ε湍流模型,构建风窗玻璃模型的计算域,并生成网格控制域。设定边界条件,重点区域采用控制混合网格,建立风窗玻璃外流场的气流模型。然后,运用COMSOL Multiphysics计算流体力学软件对气流模型进行数值仿真,分析风窗玻璃外表面的压力分布特性和附着气流速度场特性。实验结果表明,数值仿真的风窗玻璃表面附着气流特性与实验结果基本一致,验证了所建立模型的有效性。接着,采用控制变量法对气流速度和风窗玻璃倾角对流场特性的影响进行仿真。结果表明,改变气流速度只对表面压力和附着气流流速的数值产生影响,不影响风窗玻璃表面压力分布规律和附着气流的流向规律。改变风窗玻璃倾角对外流场特性影响较大,随着风窗玻璃倾角的减小,附着气流的整体流速趋于均匀。最后,研究了不同气流速度对雨滴运动的影响,这对雨滴运动的控制具有重要的参考价值和指导意义。A numerical simulation is conducted on the external flow field characteristics of windshield in this paper for revealing their effects on rain droplet movement.Firstly standard k-εturbulence model is used to set up the calculation region of windshield model and generate its mesh control region.The airflow model of external flow field of windshield is established with boundary conditions set and hybrid mesh used for key regions.Then CFD software COMSOL Multiphysics is adopted to perform numerical simulation on air flow model for analyzing the characteristics of pressure distribution and attached airflow velocity on the external surface of windshield..The results of experiment show that the simulated characteristics of attached airflow on windshield surface are basically in accordance with experiment results,verifying the effectiveness of the model built.Next,control variable scheme is utilized to simulate the effects of the airflow velocity on and the inclined angle of windshield on its flow field characteristics.The results indicate that the change of airflow velocity affects only the values of surface pressure and attached airflow velocity,but not the patterns of pressure distribution and attached airflow direction on windshield surface,while the inclined angle of windshield has larger effects on external flow field.With the reduction of windshield inclined angle,the velocities of attached airflow tends to be more uniform.Finally,the effects of different airflow velocities on the movement of rain droplets are studied with a result providing an important reference value and guiding significance for the control of rain droplet motion.

关 键 词：风窗玻璃 外流场 湍流模型 流场特性 雨滴运动 

分 类 号：U463.835[机械工程—车辆工程]