弱回転しているサッカーボールの空力特性

抄録

In ball games, the breaking ball is one of the elements that makes a game exciting. Among them, in soccer, a shoot that follows an irregular trajectory called a “knuckle ball” can greatly impact the outcome of the game, and such a trajectory is influenced by the number of rotations, the speed, and the surface structure of the ball. However, the mechanism of irregular orbiting has not been completely clarified. Therefore, the purpose of this study is to clarify their aerodynamic characteristics in a low rotational state by using a soccer ball. As a result, irregular orbits were observed in the range of 0.25 rps to 1.01 rps from the flight orbit simulation. But, at 1.01rps almost orbits flew in the direction of rotation due to the Magnus effect. One of the irregular trajectory is that the ball rotates weakly.