全尺寸汽车空气动力学风洞相关性及修正研究

Study on Correlation and Correction for Full-Scale Automotive Wind Tunnels

全尺寸汽车空气动力学风洞是汽车空气动力性能重要的研究平台与开发工具。但风洞间测试结果普遍存在差异,这对气动性能的研究与分析造成了一定的困难,因此有必要开展风洞间的横向相关性和修正研究,提高风洞测试结果的统一性和一致性。分别对德国和中国的两座全尺寸汽车风洞进行实车风洞测试,开展风洞相关性及修正研究。研究表明,对于同一工况,不同风洞间的测试结果存在一定差异,但不同工况与基础工况间差异变化趋势一致,大小相似,不同风洞间的测试结果能建立较好的相关关系,形成相关性线性函数。通过空气阻力系数C;修正方法,可以减小风洞间由结构尺寸、流场参数导致的系统性误差,修正后的风洞间空气阻力系数C;测试结果差异降低了近60%。

The full-scale automotive aerodynamic wind tunnel is an important research platform and development tool for the aerodynamic performance test of vehicles.However,the differences in wind tunnels lead to different test results and difficulties in research and analysis of aerodynamic performance.Therefore,it is necessary to carry out correlational research and correction methods for wind tunnels to improve the uniformity and consistency of wind tunnel test results.In this paper,the correlational studies and correction methods were performed for the two full-scale automotive wind tunnels in Germany and China where production vehicles were tested.The results show there are certain differences in the wind tunnel test results for the same configuration.However,the variation trend and magnitudes are in close agreements for different configurations when compared with baseline.A good correlation can be found between the two wind tunnel test results.The systematic error caused by the different structure size and flow field parameters of the wind tunnels can be reduced by C;coefficient correction,and the difference in C;coefficient can be reduced by nearly 60%after correction.