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Air fins and dimples improve tire aerodynamics

yokahamatiresThe Yokohama Tire Company is creating tire aerodynamics technology that controls the air flow around tires in motion. The new development reduces vehicle aerodynamic drag and lift which could lead to new tires with better fuel economy and safety. The technology adds fins on and side of the tire to reduce the overall drag of the air flow around the whole car.

In December 2012, Yokohama Rubber developed a technology that put fin-shaped protuberances on the inner sidewall of the tire in a radial or spoke-like pattern to reduce the aerodynamic drag inside the wheel wells.

The latest development tries to control aerodynamic flow throughout the vehicle body by using a new fin shape and placement technique that places the fin protuberances at angles near the tire’s shoulder. The fins on the tire’s outer sidewall help to reduce vehicle aerodynamic drag when on the upper part of the tire during its rotation while suppressing vehicle aerodynamic lift when on the lower part of the tire.

Yokahama also conducted a parameter study in collaboration with a team led by Professor Shigeru Obayashi of Institute of Fluid Science, Tohoku University. The study used a Supercomputer “K” to run aerodynamic simulations at different parameter values to determine the impact of changes in the parameter values for a desired result. This study led to new knowledge about the optimal placement of fins on the tire surface in order to enhance tire aerodynamics.

To date, Yokohama Rubber’s research on aerodynamics technology has to a number of new tire designs that contribute to vehicle fuel efficiency, including a dimple design that places small depressions on the side of the tire and the aforementioned fin tires, with fins located on the side of the tire.

The latest research will help to  enable more optimal placement and shaping of dimples and fins as Yokohama Rubber accelerates its research of tire designs that not only improve tires’ fuel performance but also enhance performance in many other areas.

The aerodynamic tire with new fin pattern will be on display at the YOKOHAMA display at the 44th Tokyo Motor Show 2015, to be held from 28 October at the Tokyo Big Sight in Tokyo, Japan.