基于能量守恒法测试汽车的空气阻力系数

Test of automobile air resistance coefficient based on energy conservation method

依据汽车滑行测试相关的标准,对被测车辆进行滑行阻力分析,利用能量守恒法构建被测车辆的能量耗散关系,并从中推导出被测车辆滑行试验中的空气阻力系数;根据最新发布的汽车行业标准对被测车辆进行道路滑行测试,对采集到的滑行数据进行分析计算,得出空气阻力系数的数值解析式;以实验数据和国Ⅵ计算方法作为参照,验证所得空气阻力系数计算式的合理性。研究结果表明:基于数值计算空气阻力系数所得的道路载荷与试验测试结果相比,相对误差控制在5.4%之内,且道路载荷的数值计算结果能有效逼近试验测试结果。

The sliding resistance force of the vehicle was analyzed,according to the relevant standards of automobile test,and the energy dissipation relationship of the vehicle during the test was established by the energy conservation method,and the air resistance coefficient was deduced in the coast down testing from the analysis.Based on the latest published automotive industry standards,the coast down test was applied on the sample vehicle.The equation expression of air resistance coefficient was obtained by analyzing and calculating the collected testing data.Based on China VI calculation method to calculate experimental data as a standard,the rationality of the formula for calculating the air resistance coefficient was verified.The results show that when the road load obtained by numerical calculation of air resistance coefficient is compared with the test results,the relative error is controlled within 5.4%,and the numerical results of using method can approximate the test results effectively.