Through numerical simulation and wind tunnel test, the influence of the rim opening ratio on the wind resistance of the vehicle under the wheel rotation condition is analyzed, and the recommended value of the rim opening ratio in design and development is given. Meanwhile, the correlation between the moment of ventilation resistance and the vehicle wind resistance is analyzed, and then the mechanism of wheel rotation drag reduction is analyzed. Analysis conclusions can be as following: (1) The simulation method of wheel rotation condition is credible by using the rotating wall method; (2) Under the wheel rotation condition, the smaller the opening ratio is more favorable for the vehicle wind drag reduction, and the difference of the vehicle wind drag coefficient between the rotating condition and the stationary condition will be reduced; (3) The greater the wheel ventilation resistance torque, the more conducive it is to reduce the wind resistance coefficient of the whole vehicle under rotation conditions.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |