Numerical investigation and comparison of the aerodynamic characteristics of non-pneumatic tire and pneumatic tire

A non-pneumatic tire, in which the tire pressure is replaced by an elastic support body, is called an airless tire with elastic support (ALTES). In this study, the differences in the aerodynamic characteristics between ALTES and pneumatic tire (PT) were comparatively investigated using URANS simulations based on the DrivAer model. It was found that the vehicle body drag coefficient of the vehicle equipped with ALTES was reduced by 27% compared to that of the vehicle equipped with PT and had a significant drag-reduction effect. The drag coefficient and moment coefficient of the ALTES wheels are 2 and 3.5 times those of the PT wheels, respectively, which offset the drag-reduction benefits. The drag coefficient and aerodynamic power loss of vehicles equipped with ALTES were 97–102% and 108.5%–114% of those of vehicles equipped with PT. It is reasonable and necessary to evaluate the aerodynamic performance of ALTES based on the aerodynamic power loss. By suppressing the wheel ventilation flow and reducing the wheel drag, the aerodynamic wheel cover can reduce the aerodynamic power loss of a vehicle equipped with ALTES by 12%, and the vehicle aerodynamic performance is comparable to that of a PT. •The aerodynamic performance of a non-pneumatic tire should take into account both drag and ventilation moment.•Non-pneumatic tires have a significant drag-reduction effect on the vehicle body.•Both of the drag and ventilation moment of non-pneumatic tires are higher than those of pneumatic tires.•The bluff-body shape and open-ventilated characteristics of non-pneumatic tires result in a higher level of aerodynamic loss.•Non-pneumatic tires equipped with an aerodynamic wheel cover can overcome their aerodynamic performance disadvantages.