Hello my name is Elias and I'm 14 years old. I'm a young student who is trying to find out why soccer balls knuckle. I'm currently preforming experiments. Anyway my question is, Does the size of the ball affect the boundary layer separation points? If so then maybe larger soccer balls (69.5 cm soccer balls) will have more drag (because air has to cover more distance) and might even knuckle more since there is more room for uneven lift forces to be present. Lastly just out of curiosity, how big in circumference were the two balls in the pictures above? I'm talking about the pictures in Flow separation and the drag crisis column. Thank you so much!