Abstract
An experimental study on a reduction of aerodynamic drag and an improvement of fuel economy in platoon driving was conducted to develop an Intelligent Transport System (ITS) with a good fuel economy. The test cars are two sedan cars and a microbus. Two combinations of two-car for platoon driving are tested: microbus - sedan car and sedan car - sedan car. The distance between two cars is varied from 10m to 60m in 25m/s steady driving. The reduction rate of aerodynamic drag on the sedan car was examined by measuring surface pressure on the car body. (1)Results show that the aerodynamic drag is clearly reduced on the following sedan car.(2)hen the sedan car is behind the microbus by 30m, aerodynamic drag of the sedan car is reduced by 30% which corresponds to 5% improvement in fuel economy. Based on these results, the prediction equation is derived by using the similarity power law of the free turbulent circular wake. The aerodynamic drag reduction from the equation has a good agreement with experimental results except for the case of less than 20m vehicle distance.
