There are numerous incentives for developing semi-autonomous vehicles. For instance, if cars can be coordinated into platoon formation for motorway driving there is the potential to increase road capacity, reduce traffic congestion, and lower the risk of collisions. There is also the possibility that formation driving in this way could also reduce aerodynamic drag and so improve total fuel economy for the vehicles in the platoon.
Research in the International Journal of Vehicle Systems Modelling and Testing examines this concept and investigates how vehicle shape, separation distance, and the number of vehicles in a platoon affect aerodynamic drag. Wei Gao, Zhaowen Deng, and Ying Feng of the School of Automotive Engineering at Hubei University of Automotive Technology in Shiyan, China, and Yuping He of the Department of Automotive and Mechatronics Engineering at the University of Ontario Institute of Technology in Oshawa, Ontario, Canada, carried out simulations and wind tunnel tests.
The investigation shows that irrespective of the number of vehicles in a platoon, the average aerodynamic drag on each is less than the drag measured on a vehicle driving in isolation. The more vehicles in a platoon the more beneficial is the average drag reduction on total fuel economy. Cars with what is described as a “squareback” shape as opposed to notchback or fastback, have the most to gain in fuel economy when driving in platoon, with an average drag reduction of almost 20% being observed.
The team suggests that the improved fuel economy of having semi-autonomous vehicles driving in a platoon formation on long motorway journery is worth investigating further in developing intelligent transportation systems that retain the freedom of a personal vehicle on which many people are still hooked.
Gao, W., Deng, Z., Feng, Y. and He, Y. (2022) ‘On aerodynamic drag reduction of road vehicles in platoon‘, Int. J. Vehicle Systems Modelling and Testing, Vol. 16, No. 1, pp.1-24.